[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2020.02.21"]
[Round "5"]
[White "Heijboer, Herman"]
[Black "Heun, Jetze"]
[Result "1-0"]
[ECO "A03"]
[WhiteElo "1795"]
[BlackElo "1475"]
[PlyCount "93"]
[EventDate "2019.11.08"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 g6 3. e3 Bg7 4. d4 Nf6 5. Bd3 Nc6 6. c3 Ne4 7. Nbd2 f5 8. 0-0 0-0 9. a3 e6 10. c4 Kh8 11. cxd5 exd5 12. Bxe4 fxe4 13. Ne1 Rb8 14. Nc2 b6 15. Qe2 Qh4 16. b4 Ne7 17. b5 Qg4 18. Qxg4 Bxg4 19. Re1 Bc8 20. a4 a5 21. Ba3 Re8 22. Bxe7 Rxe7 23. Rac1 Be6 24. Na3 Rc8 25. Rc3 Bf8 26. Rec1 Ree8 27. Nc2 Bd6 28. h3 Kg7 29. g4 h6 30. Kg2 Rf8 31. Nf1 Bd7 32. Ng3 Rf7 33. Na1 Bb4 34. R3c2 Ba3 35. Rf1 Bd6 36. Rb1 Be6 37. Nb3 Bb4 38. Nc1 Bd6 39. Nce2 Rd8 40. Rf1 Rc8 41. f5 Bd7 42. Nf4 gxf5 43. Ngh5+ Kh7 44. Nxd5 Be6 45. Nhf4 Bxd5 46. Nxd5 Kg6 47. Nxb6 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2020.01.24"]
[Round "4"]
[White "Hellenberg, Jan Amerik"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "A85"]
[WhiteElo "2117"]
[BlackElo "1795"]
[PlyCount "109"]
[EventDate "2019.11.08"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. c4 f5 2. Nf3 Nf6 3. Nc3 g6 4. d4 Bg7 5. b3 d6 6. Bb2 0-0 7. e3 c6 8. Bd3 a5 9. Qc2 Na6 10. a3 Nc7 11. 0-0 e6 12. Rfe1 d5 13. Ne5 Ng4 14. f4 Bxe5 15. dxe5 d4 16. Nd1 Nxe3 17. Nxe3 dxe3 18. Rxe3 Na6 19. c5 Nc7 20. Bc4 Nd5 21. Rd3 Qe7 22. Qf2 Bd7 23. Rad1 Rf7 24. Bc1 Rff8 25. Be3 Rfd8 26. Qe1 Be8 27. Qd2 Qc7 28. Bf2 Kg7 29. Bh4 Rd7 30. Qf2 Rb8 31. Bf6+ Kg8 32. h3 b5 33. cxb6 Qxb6 34. g4 Qxf2+ 35. Kxf2 Rdb7 36. gxf5 gxf5 37. Rg1+ Kf8 38. Rdg3 Bf7 39. Bg5 Ke8 40. Rc1 Rd7 41. Rd3 Kf8 42. Rd2 Kg7 43. Rd3 Rdb7 44. Ke2 h6 45. Bxd5 hxg5 46. Bc4 gxf4 47. Rg1+ Kf8 48. Kf3 Bh5+ 49. Kxf4 Bf7 50. Rd6 Rxb3 51. Bxb3 Rxb3 52. Rxc6 Rxa3 53. Rc8+ Be8 54. Rb1 Ra4+ 55. Kg5 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2019.12.20"]
[Round "3"]
[White "Heijboer, Herman"]
[Black "Bingen, Stanley"]
[Result "1-0"]
[ECO "A02"]
[WhiteElo "1795"]
[BlackElo "1168"]
[PlyCount "59"]
[EventDate "2019.11.08"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 e6 2. Nf3 Bd6 3. d3 b6 4. e4 Bb7 5. g3 Nc6 6. Bg2 e5 7. f5 f6 8. Be3 Qe7 9. Nc3 Bb4 10. 0-0 0-0-0 11. Nd5 Qd6 12. c3 Bc5 13. d4 exd4 14. cxd4 Bb4 15. a3 Nge7 16. Bf4 Ne5 17. axb4 Nxd5 18. dxe5 fxe5 19. Bxe5 Qe7 20. exd5 d6 21. Bf4 Qf6 22. Nd4 Kb8 23. Nc6+ Bxc6 24. dxc6 Qxf5 25. Rxa7 Kxa7 26. Qa4+ Kb8 27. Ra1 Qa5 28. bxa5 Rde8 29. axb6 Kc8 30. Qa8# 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2019.11.29"]
[Round "2"]
[White "Berrevoets, Jeroen"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "C54"]
[WhiteElo "2012"]
[BlackElo "1795"]
[PlyCount "91"]
[EventDate "2019.11.08"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. c3 Nf6 5. d3 d6 6. a4 a6 7. 0-0 h6 8. Be3 Ba7 9. Nbd2 0-0 10. Bxa7 Rxa7 11. Re1 Qe7 12. Nf1 Nd8 13. Nh4 Kh7 14. Ng3 g6 15. Qd2 Ra8 16. d4 Ng4 17. Nf3 Nf6 18. h3 c6 19. a5 Qc7 20. Nh4 Ne6 21. Bxe6 Bxe6 22. f4 exf4 23. Qxf4 Ng8 24. Qf2 Qe7 25. Nf3 Qf6 26. Qd2 Qg7 27. Rf1 Rad8 28. Rae1 Nf6 29. Qf4 Ng8 30. Qd2 d5 31. e5 Ne7 32. Nh4 f5 33. exf6 Rxf6 34. Rxf6 Qxf6 35. Nf3 Nf5 36. Qf4 Rf8 37. Nxf5 Bxf5 38. Ne5 Be4 39. Qxf6 Rxf6 40. Rf1 Rxf1+ 41. Kxf1 Kg7 42. g4 h5 43. Kf2 hxg4 44. hxg4 Kf6 45. Kg3 c5 46. Nd7+ 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2019.11.08"]
[Round "1"]
[White "Heijboer, Herman"]
[Black "Oosterom, Erik"]
[Result "0-1"]
[ECO "A03"]
[WhiteElo "1795"]
[BlackElo "2036"]
[PlyCount "108"]
[EventDate "2019.11.08"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 Nf6 3. e3 g6 4. d4 Bg7 5. Bd3 c5 6. c3 b6 7. Qe2 0-0 8. 0-0 a5 9. a4 Ba6 10. Nbd2 Bxd3 11. Qxd3 Qc7 12. Ne5 Nbd7 13. b3 Rac8 14. Bb2 Ne8 15. Rac1 Ndf6 16. e4 dxe4 17. Nxe4 Nxe4 18. Qxe4 Nd6 19. Qe2 cxd4 20. cxd4 Qb7 21. Nc4 Nf5 22. Ne5 Qd5 23. Rxc8 Rxc8 24. Qd3 h5 25. g3 e6 26. Rd1 Bxe5 27. dxe5 Qxd3 28. Rxd3 Ne7 29. Bc3 Nd5 30. Bd2 Kg7 31. h4 Rc2 32. Kf1 Kf8 33. Ke1 Ke7 34. Kf1 Kd7 35. Be3 Kc7 36. Bf2 Nc3 37. Be1 Ne4 38. Re3 Nc5 39. b4 axb4 40. Bxb4 Nxa4 41. Ra3 b5 42. Rd3 Nb6 43. Be7 Nd5 44. Bd6+ Kc6 45. Ra3 b4 46. Bxb4 Nxb4 47. Ra7 Kd5 48. Rxf7 Ke4 49. Rf6 Nd3 50. Rxg6 Kf3 51. Kg1 Rg2+ 52. Kf1 Rxg3 53. Rxe6 Rh3 54. Kg1 Nf2 0-1

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.06.21"]
[Round "9"]
[White "Van Tilburg, Jason"]
[Black "Heijboer, Herman"]
[Result "0-1"]
[ECO "A80"]
[BlackElo "1778"]
[PlyCount "50"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. d4 f5 2. Nf3 Nf6 3. Nc3 e6 4. g3 d5 5. Bg2 c6 6. Ne5 Nbd7 7. 0-0 Bd6 8. Bf4 Qc7 9. Nxd7 Bxd7 10. Bxd6 Qxd6 11. Qd2 0-0 12. f3 e5 13. e4 dxe4 14. Rad1 exf3 15. Bxf3 e4 16. Bg2 Nd5 17. Nxd5 cxd5 18. Qf4 Qxf4 19. Rxf4 g5 20. Rff1 f4 21. gxf4 gxf4 22. c4 f3 23. Bh1 dxc4 24. Rde1 Bh3 25. Rf2 Rae8 0-1

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.05.24"]
[Round "8"]
[White "Heijboer, Herman"]
[Black "Binnendijk, Daan"]
[Result "1/2-1/2"]
[ECO "A02"]
[WhiteElo "1778"]
[BlackElo "1876"]
[PlyCount "78"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d6 2. Nf3 c5 3. e3 Nc6 4. Bb5 Bd7 5. 0-0 a6 6. Bxc6 Bxc6 7. b3 Nf6 8. Bb2 e6 9. d3 Be7 10. Nbd2 Qc7 11. a4 b5 12. axb5 axb5 13. Qe2 0-0 14. e4 Nd7 15. Ng5 Rxa1 16. Rxa1 Bf6 17. Bxf6 Nxf6 18. Ngf3 Nd7 19. g3 Qb7 20. Nh4 Ra8 21. Rxa8+ Qxa8 22. Nf1 Qa1 23. Kf2 h6 24. Ng2 Nf6 25. Nge3 d5 26. e5 Nd7 27. Qe1 Qa2 28. Qd2 Nb6 29. g4 d4 30. Nd1 Nd5 31. Kg3 Nb4 32. c3 Qxd2 33. Nxd2 dxc3 34. Nxc3 Nxd3 35. Nce4 Kf8 36. Kf3 Bd5 37. Ke3 c4 38. bxc4 bxc4 39. Nd6 Nb2 1/2-1/2

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.04.26"]
[Round "7"]
[White "Hilarius, Sander"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "A85"]
[WhiteElo "1874"]
[BlackElo "1778"]
[PlyCount "99"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. d4 f5 2. c4 Nf6 3. Nc3 e6 4. e3 Bb4 5. Bd2 0-0 6. Bd3 d6 7. Qc2 c6 8. a3 Bxc3 9. Bxc3 a5 10. Ne2 g6 11. h4 Qe7 12. Qd2 b6 13. Rc1 Nbd7 14. b4 axb4 15. axb4 e5 16. g3 exd4 17. exd4 Ne4 18. Bxe4 Qxe4 19. 0-0 Ba6 20. Bb2 d5 21. b5 Bb7 22. cxd5 Qxd5 23. Nf4 Qxb5 24. Ne6 Qd5 25. Nc7 Qf3 26. Rc3 Qg4 27. Nxa8 Bxa8 28. Rd3 Nf6 29. Qg5 Qe2 30. Rd2 Qe4 31. f3 Qd5 32. Re2 Qd6 33. Kh2 Nd5 34. Rfe1 f4 35. Re6 fxg3+ 36. Qxg3 Qxg3+ 37. Kxg3 Bb7 38. Re8 Kg7 39. Rxf8 Kxf8 40. Ra1 c5 41. dxc5 bxc5 42. Ba3 Nb4 43. Bxb4 cxb4 44. Rb1 Bc8 45. Rxb4 Bf5 46. Rb7 Be6 47. Kf4 Bf7 48. Ke5 Kg7 49. f4 h6 50. Ra7 1-0

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.03.22"]
[Round "6"]
[White "Heijboer, Herman"]
[Black "Van Wessel, Rudy"]
[Result "0-1"]
[ECO "A03"]
[WhiteElo "1778"]
[BlackElo "2389"]
[PlyCount "102"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 Nf6 3. e3 g6 4. d4 Bg7 5. Bd3 0-0 6. 0-0 c5 7. c3 b6 8. Qe2 Bb7 9. Nbd2 Nbd7 10. Ne5 Qc7 11. b3 Ne4 12. Bb2 Nxd2 13. Qxd2 Rad8 14. Nxd7 Rxd7 15. Qe2 e6 16. Rac1 Rc8 17. Bb5 Rdd8 18. Bd3 a5 19. Bb5 Bc6 20. a4 Bxb5 21. Qxb5 Qc6 22. Qxc6 Rxc6 23. Ba3 Rdc8 24. Bb2 c4 25. bxc4 Rxc4 26. Ra1 Bf8 27. Rfc1 f6 28. Kf1 Kf7 29. Ke2 e5 30. g3 Ke6 31. h3 Bd6 32. Kd3 g5 33. fxe5 fxe5 34. g4 e4+ 35. Ke2 h5 36. Rf1 hxg4 37. hxg4 Rh8 38. Rf2 Rh4 39. Rg2 Kd7 40. Kd2 Kc6 41. Kc2 b5 42. axb5+ Kxb5 43. Bc1 Rh1 44. Bb2 Rxa1 45. Bxa1 Rc8 46. Rf2 Rf8 47. Rf5 Rxf5 48. gxf5 g4 49. Kd2 Kc4 50. f6 a4 51. f7 Kb3 0-1

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.02.15"]
[Round "5"]
[White "Beetstra, Jaap"]
[Black "Heijboer, Herman"]
[Result "1/2-1/2"]
[ECO "C33"]
[WhiteElo "1722"]
[BlackElo "1778"]
[PlyCount "85"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. e4 e5 2. f4 exf4 3. Bc4 c6 4. d4 d5 5. exd5 cxd5 6. Bd3 Nf6 7. Bxf4 Be6 8. c3 Bd6 9. Bxd6 Qxd6 10. Nf3 Nbd7 11. Nbd2 a6 12. 0-0 h6 13. a4 0-0 14. Re1 Bg4 15. Qb3 Rab8 16. Ne5 Be6 17. Qc2 Rfc8 18. Ndf3 b5 19. axb5 axb5 20. Qe2 b4 21. Ra6 Rb6 22. Rxb6 Qxb6 23. Qd2 bxc3 24. bxc3 Nxe5 25. Nxe5 Qa5 26. Rc1 Qa3 27. h3 Qa5 28. Qb2 Ra8 29. Kf2 g6 30. c4 Qa2 31. Rc2 Qxb2 32. Rxb2 dxc4 33. Bxc4 Bxc4 34. Nxc4 Ra4 35. Rc2 Nd5 36. Kf3 h5 37. g4 Kg7 38. gxh5 gxh5 39. h4 Kf6 40. Kf2 Rb4 41. Ne3 Rxd4 42. Rc6+ Ke5 43. Nxd5 1/2-1/2

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2019.01.11"]
[Round "4"]
[White "Heijboer, Herman"]
[Black "Straver, Robert"]
[Result "1/2-1/2"]
[ECO "A03"]
[WhiteElo "1778"]
[BlackElo "2131"]
[PlyCount "154"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 g6 3. e3 Bg7 4. d4 Nh6 5. Bd3 0-0 6. 0-0 Bf5 7. c3 Nd7 8. Bxf5 Nxf5 9. Qd3 c5 10. Nbd2 Rc8 11. Ne5 e6 12. Nxd7 Qxd7 13. Nf3 Rfd8 14. Bd2 Nd6 15. Be1 Ne4 16. Nd2 Nd6 17. Bf2 f5 18. Rfc1 b5 19. Qe2 c4 20. Nf3 Rb8 21. Be1 a5 22. a3 Rb6 23. h4 Ne4 24. Nd2 Nf6 25. Nf3 Rdb8 26. Rab1 Qc8 27. Kh1 Bf8 28. Ne5 Bd6 29. Nf3 Kg7 30. Kg1 Qb7 31. Ng5 Be7 32. Nf3 Ne4 33. Ng5 Bxg5 34. fxg5 Rf8 35. Qf3 Qc7 36. Qf4 e5 37. Qxe5+ Qxe5 38. dxe5 Re8 39. b3 cxb3 40. Rxb3 a4 41. Rb4 Rxe5 42. Rcb1 Nd6 43. Bg3 Re4 44. Bxd6 Rxd6 45. Rxb5 Re7 46. R1b4 Rde6 47. Rxd5 Rxe3 48. Rxa4 Rxc3 49. Rda5 Rcc7 50. Rf4 h6 51. gxh6+ Kxh6 52. Ra6 Rc1+ 53. Rf1 Rc5 54. Ra8 Re2 55. Rf3 Rcc2 56. Rg3 f4 57. Rf3 Rxg2+ 58. Kf1 Rh2 59. Kg1 Rcg2+ 60. Kf1 Ra2 61. Kg1 Rag2+ 62. Kf1 Ra2 63. Kg1 Rxh4 64. Rh8+ Kg5 65. Rxh4 Kxh4 66. Rxf4+ Kg3 67. Rf1 Rxa3 68. Rb1 g5 69. Rc1 Kh3 70. Rb1 g4 71. Rc1 Ra2 72. Rb1 Rg2+ 73. Kh1 Rd2 74. Kg1 Rd3 75. Ra1 Kg3 76. Rb1 Kf4 77. Kg2 Rg3+ 1/2-1/2

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2018.12.07"]
[Round "3"]
[White "Van der Werf, Mark"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "D26"]
[WhiteElo "2374"]
[BlackElo "1778"]
[PlyCount "73"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. d4 d5 2. c4 dxc4 3. Nf3 Nf6 4. e3 e6 5. Bxc4 c5 6. Qe2 a6 7. dxc5 Bxc5 8. e4 b5 9. Bb3 Bb7 10. e5 Nd5 11. 0-0 Nd7 12. Nc3 Nxc3 13. bxc3 Qc7 14. Bc2 Rd8 15. Bf4 Bxf3 16. Qxf3 Be7 17. Rfe1 0-0 18. Re3 g6 19. Bh6 Rfe8 20. Qf4 Nb6 21. Rf3 Bf8 22. Bxf8 Rxf8 23. Rh3 f5 24. Bb3 Nd5 25. Qd2 f4 26. Rd3 Qxe5 27. Re1 Qf5 28. h3 Kg7 29. a4 Qf6 30. axb5 axb5 31. Ra1 Nb6 32. Ra7+ Kh8 33. Rb7 Nc4 34. Bxc4 bxc4 35. Rdd7 Rfe8 36. Qd6 Qh4 37. Qe5+ 1-0

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2018.11.09"]
[Round "2"]
[White "Weidema, Luuk"]
[Black "Heijboer, Herman"]
[Result "0-1"]
[ECO "A10"]
[WhiteElo "1612"]
[BlackElo "1778"]
[PlyCount "66"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. c4 f5 2. e4 d6 3. Nc3 Nf6 4. Qc2 fxe4 5. Nxe4 e5 6. Nf3 Nxe4 7. Qxe4 Nd7 8. d4 Nf6 9. Qe2 e4 10. Bg5 Qe7 11. Nd2 Bf5 12. g3 0-0-0 13. Bg2 Re8 14. d5 h6 15. Be3 Kb8 16. h3 g5 17. b4 Bg7 18. Rc1 g4 19. h4 h5 20. a4 Bh6 21. Nb3 Bxe3 22. Qxe3 Qe5 23. Nd4 Bd7 24. b5 Rhf8 25. a5 Ng8 26. Rb1 Rf3 27. Bxf3 gxf3 28. b6 Nf6 29. bxa7+ Ka8 30. Qb3 Bc8 31. Nb5 Re7 32. 0-0 e3 33. fxe3 Qxg3+ 0-1

[Event "Leiden SB-ch 1819"]
[Site "Leiden"]
[Date "2018.10.19"]
[Round "1"]
[White "Heijboer, Herman"]
[Black "Uittenbogaard, Rob"]
[Result "1-0"]
[ECO "A03"]
[WhiteElo "1778"]
[BlackElo "1556"]
[PlyCount "39"]
[EventDate "2018.10.19"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 c5 3. e3 Nc6 4. Bb5 Bd7 5. 0-0 Nf6 6. d3 Qb6 7. a4 a6 8. Bxc6 bxc6 9. a5 Qa7 10. Qe2 e6 11. Ne5 g6 12. Nd2 Bg7 13. c3 0-0 14. Kh1 Rab8 15. e4 dxe4 16. dxe4 Ne8 17. Ndc4 Nf6 18. Nb6 Be8 19. Qc4 Rb7 20. Be3 1-0

[Event "Leiden op-A 10th"]
[Site "Leiden"]
[Date "2016.07.22"]
[Round "6"]
[White "Paays, Dominggus"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "C21"]
[WhiteElo "1402"]
[BlackElo "1856"]
[PlyCount "63"]
[EventDate "2016.07.15"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "CBM 173 Extra"]
[Source "ChessBase"]
[SourceDate "2016.08.29"]
[SourceVersion "1"]
[SourceVersionDate "2016.08.29"]
[SourceQuality "1"]

1. e4 e5 2. d4 exd4 3. c3 d5 4. exd5 Qxd5 5. cxd4 c6 6. Nf3 Nf6 7. Nc3 Qd8 8. Be2 Be7 9. 0-0 0-0 10. Be3 a5 11. Qc2 Na6 12. a3 Nc7 13. Rad1 Ncd5 14. Ne5 Be6 15. Bf3 Qc8 16. Qd2 Re8 17. Rc1 Qd8 18. Rfd1 Bf5 19. Nd3 Nxe3 20. fxe3 Bd6 21. Nf2 Qb8 22. g3 Bxg3 23. hxg3 Qxg3+ 24. Bg2 h5 25. Re1 h4 26. Nh1 Qg5 27. Qf2 h3 28. Ng3 Be6 29. Bf3 g6 30. Kh2 Kg7 31. Rg1 Bd7 32. Nh5+ 1-0

[Event "Leiden op-A 10th"]
[Site "Leiden"]
[Date "2016.07.19"]
[Round "5"]
[White "Heijboer, Herman"]
[Black "Van der Laan, Hugo"]
[Result "1-0"]
[ECO "A02"]
[WhiteElo "1856"]
[BlackElo "1747"]
[PlyCount "83"]
[EventDate "2016.07.15"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "CBM 173 Extra"]
[Source "ChessBase"]
[SourceDate "2016.08.29"]
[SourceVersion "1"]
[SourceVersionDate "2016.08.29"]
[SourceQuality "1"]

1. f4 g6 2. Nf3 Bg7 3. e3 e6 4. d4 Ne7 5. Bd3 0-0 6. 0-0 d6 7. c3 Nd7 8. e4 c5 9. dxc5 Nxc5 10. Bc2 Qc7 11. Qe1 Bd7 12. a4 b6 13. Qh4 Rae8 14. Be3 d5 15. e5 Nf5 16. Bxf5 exf5 17. Bxc5 bxc5 18. Nbd2 a5 19. Nb3 Rb8 20. Ra3 Rfe8 21. Nfd2 c4 22. Nd4 Rxb2 23. N2f3 Rb6 24. Raa1 Qd8 25. Qg3 Qe7 26. h4 Qd8 27. Rfe1 Qc8 28. Kh1 Qd8 29. Re2 Qb8 30. Ree1 Qd8 31. h5 Qe7 32. Nh4 Qd8 33. hxg6 fxg6 34. Nhf3 Qe7 35. Qf2 Reb8 36. Qg3 Qf7 37. Ng5 Qe7 38. Qf3 Re8 39. Qxd5+ Be6 40. Qxa5 Reb8 41. Ndxe6 Rxe6 42. Qd5 1-0

[Event "Leiden op-A 10th"]
[Site "Leiden"]
[Date "2016.07.18"]
[Round "4"]
[White "Mensing, Adrian"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "C44"]
[WhiteElo "1872"]
[BlackElo "1856"]
[PlyCount "67"]
[EventDate "2016.07.15"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "CBM 173 Extra"]
[Source "ChessBase"]
[SourceDate "2016.08.29"]
[SourceVersion "1"]
[SourceVersionDate "2016.08.29"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. c3 d5 4. Qa4 f6 5. Bb5 Nge7 6. exd5 Qxd5 7. d4 a6 8. Bc4 Qe4+ 9. Be3 Bd7 10. dxe5 0-0-0 11. Nbd2 Nxe5 12. Nxe4 Bxa4 13. Nxe5 fxe5 14. Ng5 Be8 15. Ne6 Rd6 16. Nxf8 Rxf8 17. Bc5 Rff6 18. Bxd6 cxd6 19. 0-0 Bc6 20. Rfe1 g5 21. a4 Ng6 22. g3 e4 23. Bf1 Ne5 24. Bg2 d5 25. b3 h5 26. Ra2 Nd3 27. Rd1 b5 28. Bf1 Ne5 29. axb5 axb5 30. Ra5 Rf3 31. Bxb5 Bxb5 32. Rxb5 Rxc3 33. Rdxd5 Rc1+ 34. Kg2 1-0

[Event "Leiden LCT op-B 09th"]
[Site "Leiden"]
[Date "2015.07.24"]
[Round "7"]
[White "Heijboer, Herman"]
[Black "Pliev, Vladimir"]
[Result "0-1"]
[ECO "A02"]
[WhiteElo "1850"]
[BlackElo "1880"]
[PlyCount "70"]
[EventDate "2015.07.17"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 g6 2. Nf3 Bg7 3. e3 d6 4. Be2 c5 5. 0-0 Nc6 6. d3 Bd7 7. c3 Nf6 8. a4 0-0 9. Na3 a6 10. Nc4 Na5 11. Nxa5 Qxa5 12. Bd2 Qc7 13. Qe1 b5 14. a5 b4 15. e4 bxc3 16. Bxc3 d5 17. Be5 Qb7 18. exd5 Nxd5 19. Bxg7 Kxg7 20. Ne5 f6 21. Nxd7 Qxd7 22. Bf3 Ra7 23. Bxd5 Qxd5 24. Qc3 Rb7 25. Rac1 Rb5 26. Rfe1 Kf7 27. Qc4 Rd8 28. Red1 Qxc4 29. Rxc4 Rxa5 30. Kf2 Rb5 31. Rd2 Rb4 32. Rxb4 cxb4 33. b3 Rc8 34. Ra2 Rc3 35. Rxa6 Rxd3 0-1

[Event "Leiden LCT op-B 09th"]
[Site "Leiden"]
[Date "2015.07.23"]
[Round "6"]
[White "Vergeer, Michiel"]
[Black "Heijboer, Herman"]
[Result "1/2-1/2"]
[ECO "C61"]
[WhiteElo "1882"]
[BlackElo "1850"]
[PlyCount "70"]
[EventDate "2015.07.17"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 Nd4 4. Nxd4 exd4 5. c3 Bc5 6. 0-0 c6 7. Be2 d6 8. d3 Ne7 9. Nd2 Bb6 10. Nf3 dxc3 11. bxc3 0-0 12. d4 d5 13. Bd3 dxe4 14. Bxe4 Bf5 15. Re1 Re8 16. Bg5 Qc8 17. Qd3 Bxe4 18. Rxe4 Ng6 19. Rae1 Qd7 20. h4 f6 21. h5 Ne7 22. Qe2 Kf7 23. Bc1 Nd5 24. Bd2 Ba5 25. c4 Bxd2 26. Qxd2 Rxe4 27. Rxe4 Nb6 28. Qe2 Re8 29. Nd2 Rxe4 30. Qxe4 g6 31. hxg6+ hxg6 32. Kf1 Qe6 33. Qxe6+ Kxe6 34. Ke2 Kf5 35. Kd3 Ke6 1/2-1/2

[Event "Leiden LCT op-B 09th"]
[Site "Leiden"]
[Date "2015.07.21"]
[Round "5"]
[White "Heijboer, Herman"]
[Black "Van den Berg, Dick"]
[Result "1/2-1/2"]
[ECO "A03"]
[WhiteElo "1850"]
[BlackElo "1896"]
[PlyCount "157"]
[EventDate "2015.07.17"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 Bg4 3. e3 Nd7 4. h3 Bxf3 5. Qxf3 Ngf6 6. d4 Ne4 7. Bd3 f5 8. Bxe4 dxe4 9. Qe2 e6 10. h4 Be7 11. g3 0-0 12. b3 c5 13. c3 a6 14. a4 b5 15. Nd2 b4 16. Bb2 bxc3 17. Bxc3 cxd4 18. Bxd4 Nc5 19. 0-0 Nd3 20. Nc4 Bf6 21. Be5 Bxe5 22. fxe5 Qb8 23. Rab1 Nxe5 24. Nxe5 Qxe5 25. Kg2 a5 26. Rfd1 Rfd8 27. Rxd8+ Rxd8 28. Rd1 Qc7 29. Rxd8+ Qxd8 30. Qb5 Kf7 31. Kf2 Qd2+ 32. Qe2 Qd5 33. Qh5+ Kf6 34. Qg5+ Kf7 35. Qh5+ Kf8 36. Qxh7 Qd2+ 37. Kg1 Qxe3+ 38. Kg2 Qf3+ 39. Kh2 e3 40. Qh8+ Kf7 41. Qd8 e2 42. Qd7+ Kf6 43. Qd8+ Ke5 44. Qxa5+ Kf6 45. Qd8+ Ke5 46. Qc7+ Ke4 47. Qc6+ Ke3 48. Qc1+ Kd3 49. Qb1+ Ke3 50. Qc1+ Kd3 51. Qb1+ Kd4 52. Qb2+ Ke4 53. Qc2+ Qd3 54. Qc6+ Ke3 55. Qc1+ Ke4 56. Qe1 Qe3 57. Kg2 Kd3 58. a5 Qd2 59. Kf2 f4 60. gxf4 Qxf4+ 61. Kg2 Qe4+ 62. Kg1 Qg4+ 63. Kh1 Qf3+ 64. Kg1 Qe3+ 65. Kg2 Kc2 66. a6 Qd2 67. Kf2 Qd4+ 68. Kg2 Qd2 69. Kf2 Kd3 70. b4 Qf4+ 71. Kg2 Qg4+ 72. Kh2 Qf3 73. Kg1 Qg4+ 74. Kh2 Qf4+ 75. Kg2 Qd2 76. Kf2 e5 77. Qb1+ Kd4 78. Qe1 Kd3 79. Qb1+ 1/2-1/2

[Event "Leiden LCT op-B 09th"]
[Site "Leiden"]
[Date "2015.07.19"]
[Round "3"]
[White "Koreman, Eric"]
[Black "Heijboer, Herman"]
[Result "1/2-1/2"]
[ECO "D27"]
[WhiteElo "1938"]
[BlackElo "1850"]
[PlyCount "64"]
[EventDate "2015.07.17"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2023"]
[Source "ChessBase"]
[SourceDate "2022.10.05"]
[SourceVersion "1"]
[SourceVersionDate "2022.10.05"]
[SourceQuality "1"]

1. d4 d5 2. c4 dxc4 3. Nc3 e6 4. e3 Nf6 5. Nf3 c5 6. Bxc4 a6 7. a4 Nbd7 8. 0-0 Bd6 9. Qe2 Qc7 10. h3 0-0 11. e4 cxd4 12. Nxd4 Nb6 13. Bb3 e5 14. Nc2 h6 15. Ne3 Be6 16. Bxe6 fxe6 17. a5 Nbd7 18. Nc4 Bc5 19. Be3 Rac8 20. Bxc5 Qxc5 21. Ra4 Rc6 22. Rd1 b5 23. axb6 Nxb6 24. Nxb6 Qxb6 25. Rda1 Ra8 26. Rd1 Rb8 27. Rd2 Ra8 28. Ra1 Rd6 29. Rxd6 Qxd6 30. Rd1 Qc6 31. Qd3 Rb8 32. Rd2 a5 1/2-1/2

[Event "Leiden LCT op-A 5th"]
[Site "Leiden"]
[Date "2011.07.17"]
[Round "9"]
[White "Borst, Filip"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "C45"]
[WhiteElo "2001"]
[PlyCount "29"]
[EventDate "2011.07.08"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "CBM 143 Extra"]
[Source "ChessBase"]
[SourceDate "2011.08.29"]
[SourceVersion "1"]
[SourceVersionDate "2011.08.29"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Qh4 5. Nb5 Qxe4+ 6. Be2 Kd8 7. 0-0 a6 8. Bf3 Qg6 9. N5c3 Bd6 10. Be3 Nf6 11. Nd2 h5 12. Nc4 Ne8 13. Re1 f6 14. Nxd6 Nxd6 15. Qxd6 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.06.29"]
[Round "7"]
[White "Zeevaarder, Michael"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "B12"]
[WhiteElo "1810"]
[BlackElo "1745"]
[PlyCount "71"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. g4 Bg6 5. h4 h6 6. f4 e6 7. Bd3 Bxd3 8. Qxd3 Qc7 9. b3 Nd7 10. Nf3 Be7 11. Nbd2 0-0-0 12. Bb2 Kb8 13. a4 Rc8 14. c4 Bb4 15. Rc1 dxc4 16. bxc4 Qd8 17. Ke2 Be7 18. Ba3 f6 19. Bxe7 Nxe7 20. Ne4 f5 21. Nd6 fxg4 22. Nd2 Qf8 23. Nxc8 Nxc8 24. Qe4 Ne7 25. Rb1 Qf5 26. h5 Rf8 27. Qxf5 Nxf5 28. Kd3 Rd8 29. Ne4 Kc7 30. Nd6 b6 31. Rhg1 Nxd6 32. exd6+ Kxd6 33. Rxg4 Nf6 34. Rxg7 Nxh5 35. Rxa7 Rb8 36. Rxb6 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.06.22"]
[Round "6"]
[White "Bakker, Joop"]
[Black "Heijboer, Herman"]
[Result "0-1"]
[ECO "A03"]
[WhiteElo "1942"]
[BlackElo "1745"]
[PlyCount "92"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 d5 2. b3 c5 3. e3 Nc6 4. Nf3 Bg4 5. Bb2 e6 6. d3 Nf6 7. Be2 Bxf3 8. Bxf3 Bd6 9. c4 a6 10. Nc3 Bc7 11. 0-0 0-0 12. Ba3 b6 13. d4 cxd4 14. Bxf8 dxc3 15. Ba3 b5 16. Bc5 Bb6 17. Bxb6 Qxb6 18. cxd5 exd5 19. Qc1 b4 20. Rd1 Rd8 21. Kh1 Ne4 22. Bxe4 dxe4 23. Rxd8+ Qxd8 24. a3 Qd3 25. axb4 Nxb4 26. Qe1 Nc2 27. Rxa6 Qxa6 28. Qxc3 Qa1+ 29. Qxa1 Nxa1 30. b4 Kf8 31. Kg1 Nc2 32. b5 Ke7 33. Kf2 f5 34. Ke2 Kd6 35. g4 g6 36. b6 Kc6 37. Kd2 Nb4 38. gxf5 gxf5 39. b7 Kxb7 40. Kc3 Nd5+ 41. Kd4 Nxe3 42. Kxe3 Kc6 43. Kd4 Kd6 44. h4 Ke6 45. Kc4 Kf6 46. Kd4 Kg6 0-1

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.06.15"]
[Round "5"]
[White "Heijboer, Herman"]
[Black "Thissen, Thomas"]
[Result "0-1"]
[ECO "A02"]
[WhiteElo "1745"]
[BlackElo "1988"]
[PlyCount "118"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 c5 2. Nf3 Nc6 3. e3 d6 4. Bb5 Bd7 5. b3 a6 6. Bxc6 Bxc6 7. Bb2 Nf6 8. 0-0 e6 9. d3 Be7 10. Nbd2 b5 11. c4 0-0 12. Qe2 a5 13. h3 a4 14. g4 a3 15. Bc1 b4 16. Rf2 Nd7 17. Rb1 f5 18. gxf5 Rxf5 19. Ne4 h6 20. Ng3 Rf8 21. Bd2 Qe8 22. Kh2 Nf6 23. Rg1 Nh5 24. Nxh5 Qxh5 25. Nd4 Qxe2 26. Nxe2 Bh4 27. Ng3 Kh8 28. Rff1 Ra7 29. Ne4 Bxe4 30. dxe4 Raf7 31. Rg6 Rf6 32. Rfg1 Rxg6 33. Rxg6 Rf6 34. Rg4 g5 35. Kg1 Kg7 36. Rg2 Kf7 37. Kf1 Ke7 38. Ke2 Kd7 39. Kf3 Kc6 40. Ke2 Rf8 41. Kd3 Rc8 42. fxg5 hxg5 43. Ke2 Rf8 44. Rh2 Kd7 45. Rg2 Ke7 46. Rh2 Kf6 47. Be1 Bxe1 48. Kxe1 Ke5 49. Ke2 Kxe4 50. Rg2 Rh8 51. Rxg5 Rxh3 52. Rg4+ Kf5 53. Rg2 Rh4 54. Kf3 d5 55. cxd5 exd5 56. Rd2 Ke5 57. Rg2 c4 58. Rg5+ Kd6 59. bxc4 Rxc4 0-1

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.06.08"]
[Round "4"]
[White "Aalders, Peter"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "D21"]
[WhiteElo "1931"]
[BlackElo "1745"]
[PlyCount "41"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. d4 d5 2. c4 dxc4 3. e3 c5 4. Nf3 cxd4 5. Bxc4 Nf6 6. exd4 Bg4 7. Bxf7+ Kxf7 8. Ne5+ Ke8 9. Nxg4 Nc6 10. Nxf6+ exf6 11. Be3 Bd6 12. Nc3 Qd7 13. 0-0 h5 14. Re1 Kf8 15. Rc1 a6 16. Ne4 Kg8 17. Qb3+ Kh7 18. Nxd6 Qxd6 19. Qxb7 Ne7 20. Rc5 Rhb8 21. Qf3 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.06.01"]
[Round "3"]
[White "Heijboer, Herman"]
[Black "Kors, Hans"]
[Result "1-0"]
[ECO "A03"]
[WhiteElo "1745"]
[BlackElo "1852"]
[PlyCount "83"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 Bg4 3. e3 Nc6 4. Bb5 a6 5. Bxc6+ bxc6 6. d3 Nf6 7. Nbd2 e6 8. 0-0 Bc5 9. Qe1 Bxf3 10. Nxf3 Nd7 11. Kh1 0-0 12. b3 f6 13. Bb2 Qe7 14. e4 Rae8 15. a4 e5 16. f5 Rb8 17. Qe2 Rfd8 18. h3 a5 19. g4 Nb6 20. Rad1 Bd6 21. Bc1 Ba3 22. Bd2 Bb4 23. Rg1 Bxd2 24. Nxd2 Nd7 25. Rg2 h6 26. h4 Nc5 27. Rdg1 Rd6 28. g5 fxg5 29. hxg5 hxg5 30. Rxg5 Rh6+ 31. Rh5 Qf6 32. Qh2 Rxh5 33. Qxh5 dxe4 34. Rg6 Qf7 35. Nxe4 Nxe4 36. dxe4 Rd8 37. f6 Rd1+ 38. Kg2 Rd2+ 39. Kf3 Kf8 40. Qh8+ Qg8 41. fxg7+ Kf7 42. Rf6+ 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2010.05.18"]
[Round "1"]
[White "Heijboer, Herman"]
[Black "Termeulen, Albert"]
[Result "0-1"]
[ECO "A02"]
[WhiteElo "1745"]
[BlackElo "2092"]
[PlyCount "92"]
[EventDate "2010.05.18"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 c5 2. Nf3 Nc6 3. e3 g6 4. Bb5 Bg7 5. Bxc6 bxc6 6. 0-0 Nf6 7. d3 0-0 8. Nbd2 d5 9. Ne5 Qb6 10. Kh1 c4 11. e4 cxd3 12. cxd3 Ba6 13. Qf3 Rad8 14. Re1 Ne8 15. exd5 cxd5 16. Nb3 Bb7 17. d4 Nd6 18. Bd2 Nc4 19. Bc3 f6 20. Ng4 e5 21. fxe5 fxe5 22. Qd1 e4 23. Nc5 Bc8 24. b3 Nd6 25. h3 Nf5 26. Qd2 h5 27. Ne3 Bh6 28. Ba5 Qf6 29. Bxd8 Rxd8 30. Qc3 Ng3+ 31. Kg1 Qg5 32. Nf1 Nf5 33. Rad1 Nh4 34. Qg3 Qf6 35. Qe5 Qxe5 36. dxe5 Nf5 37. Nxe4 d4 38. Nc5 Bf8 39. b4 a5 40. a3 axb4 41. axb4 Rd5 42. Ne3 Nxe3 43. Rxe3 Rxc5 44. bxc5 dxe3 45. Kf1 Ba6+ 46. Ke1 Bxc5 0-1

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2009.06.30"]
[Round "7"]
[White "De Mooij, Marco"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "C84"]
[WhiteElo "1902"]
[PlyCount "85"]
[EventDate "2009.05.19"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. 0-0 Be7 6. c3 b5 7. Bc2 0-0 8. d4 d6 9. h3 Ne8 10. Re1 Bf6 11. Be3 Bd7 12. Nbd2 g6 13. Nf1 Ng7 14. Bh6 Re8 15. g4 Be7 16. Ng3 exd4 17. cxd4 Nb4 18. Bb3 a5 19. a3 a4 20. axb4 axb3 21. Qxb3 Rxa1 22. Rxa1 Ne6 23. Qe3 Bf8 24. d5 Bxh6 25. Qxh6 Nf8 26. Rc1 f6 27. Nd4 Re7 28. Qe3 Rg7 29. Kh2 Qc8 30. Qc3 Be8 31. Ra1 h6 32. f4 h5 33. gxh5 Rh7 34. Ra5 Qb8 35. Nc6 Qb6 36. Nd4 gxh5 37. Ngf5 Ng6 38. Qg3 Kf7 39. Ra1 h4 40. Qg4 Bd7 41. Nh6+ Rxh6 42. Qxd7+ Ne7 43. Qe6+ 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2009.06.23"]
[Round "6"]
[White "Heijboer, Herman"]
[Black "Wagemans, Ed"]
[Result "1/2-1/2"]
[ECO "A02"]
[BlackElo "1958"]
[PlyCount "85"]
[EventDate "2009.05.19"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 Nf6 2. Nf3 g6 3. b3 Bg7 4. Bb2 c5 5. e3 Nc6 6. Bb5 a6 7. Bxc6 bxc6 8. 0-0 d6 9. d3 0-0 10. Qe1 a5 11. a4 Ba6 12. Nbd2 Qc7 13. Qh4 Rab8 14. Bxf6 Bxf6 15. Ng5 Bxg5 16. Qxg5 d5 17. Qh6 e6 18. Nf3 f6 19. Qh3 Qe7 20. Rfe1 e5 21. fxe5 fxe5 22. e4 c4 23. exd5 cxb3 24. cxb3 Bxd3 25. Nxe5 Qc5+ 26. Kh1 Bf5 27. Qg3 Qxd5 28. Qc3 Be4 29. Rxe4 Qxe4 30. Nd7 Rf2 31. Qg3 Rbf8 32. Nxf8 Rxf8 33. Re1 Qb4 34. h3 c5 35. Qe3 Qd4 36. Qe6+ Rf7 37. Rf1 Qd7 38. Qc4 Qc7 39. Rxf7 Qxf7 40. Qxc5 Qf1+ 41. Kh2 Qf4+ 42. Kg1 Qd2 43. Qc4+ 1/2-1/2

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2009.06.16"]
[Round "5"]
[White "Geertsma, Folkert Jan"]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "A10"]
[WhiteElo "1931"]
[PlyCount "75"]
[EventDate "2009.05.19"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. c4 f5 2. h3 Nf6 3. g4 d5 4. g5 Ne4 5. d3 Nc5 6. cxd5 Qxd5 7. Nf3 e5 8. Nc3 Qe6 9. Bg2 Bd6 10. Nd2 c6 11. Nc4 Nba6 12. a3 Nc7 13. b4 Nd7 14. Rb1 Nb6 15. Nxd6+ Qxd6 16. Bb2 Be6 17. Na4 Nxa4 18. Qxa4 0-0 19. Qc2 Nd5 20. Qc5 Qd8 21. h4 Qc7 22. Rc1 Rac8 23. Qxa7 Nf4 24. Bf3 Bd5 25. Bxd5+ Nxd5 26. Qc5 e4 27. dxe4 fxe4 28. e3 Qf7 29. Rf1 Qh5 30. Qd4 Rf7 31. b5 Qxh4 32. bxc6 bxc6 33. Rc4 Qxg5 34. Qxe4 Rcf8 35. Bd4 Nf6 36. Qe5 Qxe5 37. Bxe5 Ng4 38. Rxg4 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2009.06.02"]
[Round "3"]
[White "Heijboer, Herman"]
[Black "Renes, David"]
[Result "1-0"]
[ECO "A02"]
[BlackElo "972"]
[PlyCount "57"]
[EventDate "2009.05.19"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 Nc6 2. e3 g6 3. Nf3 f6 4. b3 Bg7 5. Bb2 d6 6. Bb5 a6 7. Bxc6+ bxc6 8. 0-0 Bb7 9. d3 Nh6 10. Qe2 a5 11. a4 c5 12. e4 Qd7 13. Nbd2 Ba6 14. Rae1 e5 15. fxe5 fxe5 16. Ng5 Qg4 17. Qxg4 Nxg4 18. Ne6 Rc8 19. Nxg7+ Kd7 20. Rf7+ Kc6 21. Ne6 Nh6 22. Rg7 Ng8 23. Rf1 Kb6 24. Rff7 Nh6 25. Rxc7 Rxc7 26. Nxc7 Bc8 27. Nc4+ Kc6 28. Nb5 Be6 29. Rc7# 1-0

[Event "Leiden SB-ch"]
[Site "Leiden"]
[Date "2009.05.19"]
[Round "1"]
[White "Heijboer, Herman"]
[Black "Leeuwenburgh, Evert"]
[Result "0-1"]
[ECO "A03"]
[BlackElo "2056"]
[PlyCount "126"]
[EventDate "2009.05.19"]
[EventType "swiss"]
[EventRounds "7"]
[EventCountry "NED"]
[SourceTitle "EXT 2012"]
[Source "ChessBase"]
[SourceDate "2011.11.24"]
[SourceVersion "1"]
[SourceVersionDate "2011.11.24"]
[SourceQuality "1"]

1. f4 d5 2. Nf3 Nf6 3. e3 Bf5 4. b3 e6 5. Bb2 c6 6. Be2 Nbd7 7. 0-0 Bd6 8. a4 a5 9. Nd4 Bg6 10. Ba3 Qc7 11. Bxd6 Qxd6 12. c4 0-0 13. Nc3 dxc4 14. bxc4 e5 15. fxe5 Nxe5 16. Nf5 Qd7 17. g4 Bxf5 18. gxf5 Nd3 19. Bxd3 Qxd3 20. Qe2 Rad8 21. Qxd3 Rxd3 22. Rf2 Rfd8 23. Ra2 Ng4 24. Re2 Ne5 25. Ne4 Nxc4 26. Nc5 Rxd2 27. Nxb7 Rxa2 28. Rxa2 Rd1+ 29. Kf2 Rc1 30. Ke2 Rc3 31. Kf2 Kf8 32. e4 Ke7 33. e5 Nxe5 34. Nxa5 Kd7 35. Kg2 Nd3 36. Kf1 Kc7 37. Rd2 Kb6 38. Nc4+ Rxc4 39. Rxd3 Rxa4 40. Rf3 Rh4 41. h3 Rh6 42. Ke2 Rf6 43. Kd2 g6 44. Rb3+ Kc5 45. fxg6 hxg6 46. Rb7 Kc4 47. Re7 Rd6+ 48. Kc2 f5 49. Rf7 Kd4 50. h4 Ke4 51. h5 gxh5 52. Rh7 Rf6 53. Rxh5 Kf3 54. Kd2 c5 55. Ke1 c4 56. Rh3+ Ke4 57. Rh8 f4 58. Re8+ Kd3 59. Rd8+ Kc2 60. Kf2 f3 61. Rd7 c3 62. Rd8 Kc1 63. Rd7 c2 0-1

[Event "NED-ch H415 corr"]
[Site "Netherlands"]
[Date "1989.??.??"]
[Round "?"]
[White "Uffing, P."]
[Black "Heijboer, Herman"]
[Result "1-0"]
[ECO "D20"]
[PlyCount "49"]
[EventDate "1989.??.??"]
[EventType "tourn (corr)"]
[EventRounds "10"]
[EventCountry "NED"]
[SourceTitle "Corr Nr. 1"]
[Source "ChessBase"]
[SourceDate "1997.09.01"]
[SourceVersion "2"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 dxc4 5. Bxc4 a6 6. Nf3 b5 7. Bxf7+ Kxf7 8. Ne5+ Ke8 9. Qf3 Nf6 10. Qxa8 Qc7 11. 0-0 Bb7 12. Qa7 Nc6 13. Nxc6 Qxc6 14. f3 g6 15. Bf4 Nd5 16. Rc1 Qd7 17. Be5 Rg8 18. Nc3 Nb4 19. Ne4 Nc6 20. Qb6 Bg7 21. Bxg7 Rxg7 22. d5 Nd8 23. Rc7 Qf5 24. Nd6+ exd6 25. Re1+ 1-0

[Event "NED corr"]
[Site "Netherlands"]
[Date "1985.??.??"]
[Round "?"]
[White "Heijboer, Herman"]
[Black "Bakema, Aeilko"]
[Result "1-0"]
[ECO "B05"]
[PlyCount "105"]
[EventDate "1985.??.??"]
[EventType "tourn (corr)"]
[EventRounds "10"]
[EventCountry "NED"]
[SourceTitle "Corr Nr. 1"]
[Source "ChessBase"]
[SourceDate "1997.09.01"]
[SourceVersion "2"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 Bg4 5. Be2 c6 6. Ng5 Bf5 7. Bg4 Bxg4 8. Qxg4 dxe5 9. dxe5 e6 10. 0-0 Nd7 11. c4 Ne7 12. Rd1 h6 13. Ne4 Ng6 14. Nd6+ Bxd6 15. exd6 Qh4 16. Qxh4 Nxh4 17. Nc3 0-0-0 18. b4 b6 19. a4 Ne5 20. c5 bxc5 21. bxc5 Rd7 22. Rb1 Rb7 23. Ba3 Rxb1 24. Rxb1 Nhg6 25. Bc1 Nd7 26. Be3 Nge5 27. Ne2 Nd3 28. Nd4 N7xc5 29. Nxc6 Kd7 30. Bxc5 Kxc6 31. Bxa7 Ra8 32. Rb6+ Kd7 33. Rb7+ Kxd6 34. Rxf7 g6 35. a5 Ne5 36. Rg7 Nd7 37. Be3 Rxa5 38. h3 h5 39. Rxg6 Rf5 40. g4 hxg4 41. hxg4 Rf7 42. Kg2 Rf6 43. Rg5 e5 44. Kg3 Ke6 45. Kh4 Rf3 46. Rg6+ Kf7 47. Rc6 Nf6 48. g5 Nd5 49. Kg4 e4 50. g6+ Kg7 51. Bd4+ Kf8 52. Rc8+ Ke7 53. g7 1-0

[Event "NED corr"]
[Site "Netherlands"]
[Date "1985.??.??"]
[Round "?"]
[White "Heijboer, Herman"]
[Black "Van Oosten, PFM"]
[Result "1-0"]
[ECO "C89"]
[PlyCount "85"]
[EventDate "1985.??.??"]
[EventType "tourn (corr)"]
[EventRounds "10"]
[EventCountry "NED"]
[SourceTitle "Corr Nr. 1"]
[Source "ChessBase"]
[SourceDate "1997.09.01"]
[SourceVersion "2"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. 0-0 Be7 6. Re1 b5 7. Bb3 0-0 8. c3 d5 9. exd5 Nxd5 10. Nxe5 Nxe5 11. Rxe5 c6 12. d4 Bd6 13. Re1 Qh4 14. g3 Qh3 15. Be3 Bg4 16. Qd3 Rae8 17. Nd2 f5 18. f4 Kh8 19. Bxd5 cxd5 20. Qf1 Qh5 21. a4 bxa4 22. Rxa4 Re6 23. Rxa6 Rfe8 24. Qb5 h6 25. Qxd5 Rxe3 26. Rxe3 Rxe3 27. Rxd6 Bh3 28. Rd8+ Re8 29. Rxe8+ Qxe8 30. Kf2 Qa4 31. Ke3 Qc2 32. c4 Qxb2 33. Kd3 Bg4 34. Qb5 Qa3+ 35. Kc2 Qa1 36. d5 Bd1+ 37. Kd3 Qa3+ 38. Kd4 Bc2 39. Qe8+ Kh7 40. Qe3 Qb2+ 41. Kc5 Ba4 42. h3 Qb7 43. Kd4 1-0

[Event "NED corr"]
[Site "Netherlands"]
[Date "1985.??.??"]
[Round "?"]
[White "Zomer, J."]
[Black "Heijboer, Herman"]
[Result "0-1"]
[ECO "A99"]
[PlyCount "110"]
[EventDate "1985.??.??"]
[EventType "tourn (corr)"]
[EventRounds "10"]
[EventCountry "NED"]
[SourceTitle "Corr Nr. 1"]
[Source "ChessBase"]
[SourceDate "1997.09.01"]
[SourceVersion "2"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. c4 f5 2. Nf3 Nf6 3. g3 e6 4. Bg2 Be7 5. 0-0 0-0 6. d4 d6 7. Nc3 Qe8 8. b3 a5 9. Bb2 Na6 10. e3 c6 11. Ne1 e5 12. Na4 Bd8 13. dxe5 dxe5 14. Qd2 Bc7 15. f4 e4 16. Nc2 Be6 17. c5 Rd8 18. Qe2 Nd5 19. Bd4 Qe7 20. h4 g6 21. Rab1 Ra8 22. Rfc1 h6 23. a3 Bd8 24. Ne1 Qf7 25. Qb2 g5 26. hxg5 hxg5 27. Bf1 Qg6 28. Ng2 Kf7 29. Bxa6 bxa6 30. Kf2 gxf4 31. Nxf4 Nxf4 32. exf4 Qh5 33. Rg1 Qf3+ 34. Ke1 Rg8 35. Qe2 Rxg3 36. Qxf3 Rxf3 37. Rg7+ Kf8 38. Ke2 Bxb3 39. Rh1 Bc4+ 40. Ke1 Rf1+ 41. Rxf1 Bh4+ 42. Kd2 Bxf1 43. Rh7 Rd8 44. Ke3 Rxd4 45. Kxd4 Bf2+ 46. Ke5 e3 47. Nc3 Be1 48. Kd4 e2 49. Nxe2 Bxe2 50. Rh3 Bf2+ 51. Ke5 Bxc5 52. Kxf5 Bd4 53. Ke4 c5 54. Rh2 Bb5 55. Rh6 a4 0-1

[Event "NED-ch H142 corr"]
[Site "Netherlands"]
[Date "1980.??.??"]
[Round "?"]
[White "Heijboer, Herman"]
[Black "Phillhock"]
[Result "1/2-1/2"]
[ECO "D93"]
[PlyCount "113"]
[EventDate "1980.??.??"]
[EventType "tourn (corr)"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. Bf4 Bg7 5. Nf3 0-0 6. Rc1 c6 7. e3 Bg4 8. Qb3 Bxf3 9. gxf3 Qd7 10. h4 e6 11. Be5 Nh5 12. Bxg7 Nxg7 13. f4 Qe7 14. Be2 h5 15. c5 Na6 16. Kd2 Rab8 17. Rcg1 Nc7 18. Na4 Nce8 19. Rg2 Nf6 20. Qc2 Kh7 21. b3 Rg8 22. Bf3 Nf5 23. Nb2 Nd7 24. Rg5 Kh6 25. Be2 f6 26. Rg2 e5 27. dxe5 fxe5 28. fxe5 Nxc5 29. Bd3 Ne4+ 30. Bxe4 Qb4+ 31. Ke2 Qxe4 32. Qxe4 dxe4 33. Nc4 Rge8 34. Nd6 Nxd6 35. exd6 Rbd8 36. Rd1 Rd7 37. Rg5 b6 38. b4 Kg7 39. Rdg1 Rxd6 40. Rxh5 Rh8 41. Rxh8 Kxh8 42. Rg5 Re6 43. h5 gxh5 44. Rxh5+ Kg7 45. Rf5 Kg6 46. Rf4 Re5 47. a3 Kg5 48. Rf7 a5 49. Rf4 a4 50. f3 exf3+ 51. Rxf3 c5 52. bxc5 Rxc5 53. Rf4 b5 54. Kd2 Re5 55. Kd3 Rd5+ 56. Rd4 Rc5 57. Rf4 1/2-1/2

