[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2020.09.25"]
[Round "6"]
[White "Oei, Ik"]
[Black "Dobbelaar, Ruud"]
[Result "1-0"]
[ECO "A30"]
[WhiteElo "2003"]
[BlackElo "1786"]
[PlyCount "53"]
[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. Nf3 c5 2. c4 Nc6 3. b3 e5 4. d3 d6 5. Bb2 f5 6. Nbd2 Nf6 7. e3 Be7 8. Be2 0-0 9. 0-0 e4 10. dxe4 Nxe4 11. Nxe4 fxe4 12. Nd2 Bf5 13. Qb1 Bf6 14. a3 Re8 15. Rd1 Bxb2 16. Qxb2 Ne5 17. Qc2 Qh4 18. g3 Qh3 19. Bf1 Qh5 20. Qc3 Bg4 21. Rdb1 Rf8 22. Bg2 Rxf2 23. Rf1 Rxf1+ 24. Rxf1 Be2 25. Rf4 g5 26. Nxe4 Ng4 27. Rxg4 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2020.02.21"]
[Round "5"]
[White "Ada, Onur"]
[Black "Oei, Ik"]
[Result "0-1"]
[ECO "B23"]
[WhiteElo "1566"]
[BlackElo "2003"]
[PlyCount "80"]
[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 c5 2. Nc3 Nc6 3. f4 g6 4. Nf3 Bg7 5. Bc4 d6 6. h3 e6 7. Bb5 Nge7 8. d3 0-0 9. Bxc6 Nxc6 10. 0-0 Rb8 11. a3 b5 12. Bd2 a5 13. Rb1 b4 14. axb4 axb4 15. Ne2 Qb6 16. Be3 Nd4 17. Nexd4 cxd4 18. Bd2 Bd7 19. Kh1 Rfc8 20. e5 Bc6 21. c3 Bxf3 22. Qxf3 bxc3 23. bxc3 Qxb1 24. Rxb1 Rxb1+ 25. Kh2 dxc3 26. Bxc3 Rxc3 27. Qa8+ Bf8 28. d4 d5 29. Qa2 Rb4 30. f5 gxf5 31. Qd2 Rc8 32. h4 h6 33. Qf2 Rcc4 34. Qg3+ Kh7 35. Qf3 Rxd4 36. g3 Rd2+ 37. Kh3 Rbb2 38. Qh1 Rh2+ 39. Qxh2 Rxh2+ 40. Kxh2 Kg6 0-1

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2020.01.24"]
[Round "4"]
[White "Oei, Ik"]
[Black "Weiland, Harro"]
[Result "0-1"]
[ECO "A13"]
[WhiteElo "2003"]
[BlackElo "1762"]
[PlyCount "112"]
[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. Nf3 Nf6 2. c4 e6 3. b3 d5 4. Bb2 Nc6 5. e3 Bb4 6. a3 Be7 7. b4 a5 8. b5 Nb8 9. Nc3 0-0 10. Qb3 c6 11. d4 Nbd7 12. Be2 Ne4 13. Nxe4 dxe4 14. Nd2 f5 15. 0-0 c5 16. Rfd1 Bd6 17. g3 b6 18. Bf1 Qe7 19. Bg2 Bb7 20. a4 Rad8 21. Qc2 cxd4 22. exd4 e5 23. Nb3 Bb4 24. Rac1 Rc8 25. d5 Qd6 26. Qe2 Nc5 27. Nxc5 Bxc5 28. Rc2 Rc7 29. Kh1 Bc8 30. Qh5 g6 31. Qh6 Re8 32. h4 Rg7 33. Bc1 Bd7 34. Be3 Bxe3 35. Qxe3 Rc8 36. Bf1 f4 37. Qe1 Bg4 38. Be2 Bf3+ 39. Bxf3 exf3 40. Qe4 fxg3 41. fxg3 Rf8 42. Rf1 Qd7 43. Rxf3 Rxf3 44. Qxf3 Rf7 45. Qg2 Qg4 46. Kh2 e4 47. c5 bxc5 48. Rxc5 e3 49. Rc2 Qd4 50. Kh3 Rf2 51. Rxf2 exf2 52. Qf3 Qxa4 53. Qd3 Qa1 54. d6 f1Q+ 55. Qxf1 Qxf1+ 56. Kh2 Qxb5 0-1

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2019.12.20"]
[Round "3"]
[White "Van der Marel, Lambertus"]
[Black "Oei, Ik"]
[Result "1-0"]
[ECO "A30"]
[WhiteElo "2086"]
[BlackElo "2003"]
[PlyCount "71"]
[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. Nf3 c5 2. c4 Nf6 3. Nc3 e6 4. g3 b6 5. Bg2 Bb7 6. 0-0 a6 7. d3 d6 8. e4 Nbd7 9. Nh4 Qc7 10. a3 Be7 11. f4 0-0 12. Bd2 Bc6 13. g4 Rab8 14. g5 Ne8 15. Qg4 b5 16. Nd5 Qd8 17. b4 g6 18. Nxe7+ Qxe7 19. Rae1 Ng7 20. Bc3 Rbe8 21. f5 Qd8 22. Qg3 Qb8 23. Bxg7 Kxg7 24. f6+ Kh8 25. cxb5 axb5 26. Rc1 Rc8 27. Nf3 e5 28. Qh4 Qa7 29. Kh1 Qxa3 30. bxc5 Nxc5 31. Qh6 Rg8 32. d4 exd4 33. Nxd4 Bxe4 34. Bxe4 Nxe4 35. Rxc8 Nf2+ 36. Rxf2 1-0

[Event "Leiden SB-ch 1920"]
[Site "Leiden"]
[Date "2019.11.29"]
[Round "2"]
[White "Oei, Ik"]
[Black "De Mooij, Marco"]
[Result "1-0"]
[ECO "A25"]
[WhiteElo "2003"]
[BlackElo "1816"]
[PlyCount "117"]
[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 e5 2. g3 g6 3. Bg2 Bg7 4. Nc3 Nc6 5. e3 d6 6. Nge2 Be6 7. Nd5 Qd7 8. Nec3 Nf6 9. d4 exd4 10. exd4 Bg4 11. f3 Bh3 12. Bxh3 Qxh3 13. Nf4 Qd7 14. 0-0 0-0 15. Be3 Rfe8 16. Bf2 Qf5 17. Kg2 a6 18. Nfd5 Nxd5 19. Nxd5 Qd7 20. Qd2 Ne7 21. Nc3 d5 22. c5 Nc6 23. Rab1 Re6 24. b4 Rae8 25. a3 Ne7 26. g4 f5 27. g5 c6 28. Ne2 Nc8 29. Nf4 R6e7 30. Rfe1 Qd8 31. h4 Kf7 32. Rxe7+ Rxe7 33. Re1 Qe8 34. Rxe7+ Qxe7 35. Qe3 Qxe3 36. Bxe3 b5 37. Kf2 Ne7 38. Ke2 Bh8 39. Kd3 Bg7 40. Ne2 Ke6 41. Bf4 Nc8 42. Ke3 Ne7 43. Nc1 Nc8 44. Nd3 Bf8 45. Be5 Be7 46. Bb8 Bf8 47. Ne5 Ne7 48. Bd6 Bg7 49. Nd3 Nc8 50. Be5 Bf8 51. Bf6 Be7 52. Bxe7 Kxe7 53. Ne5 Na7 54. Kf4 Ke6 55. Kg3 Ke7 56. h5 gxh5 57. Kh4 Ke6 58. Kxh5 f4 59. Kg4 1-0

