[Event "W-ch H GT39 corr"]
[Site "ICCF corr"]
[Date "1998.??.??"]
[Round "?"]
[White "Eshoj, Peter"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "A40"]
[PlyCount "37"]
[EventDate "1998.??.??"]
[EventType "tourn (corr)"]
[EventRounds "14"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 f6 2. e4 e6 3. Nc3 Bb4 4. Bd2 Nc6 5. a3 Bxc3 6. Bxc3 d5 7. Bd3 dxe4 8. Bxe4 Nge7 9. Qh5+ g6 10. Qh6 Nxd4 11. 0-0-0 e5 12. Qg7 Rf8 13. Bb4 a5 14. Bc5 Bg4 15. Nf3 Bxf3 16. Bxf3 c6 17. Rxd4 exd4 18. Re1 Rf7 19. Qg8+ 1-0

[Event "W-ch H GT39 corr"]
[Site "ICCF corr"]
[Date "1998.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Nachtigall, Frank"]
[Result "0-1"]
[ECO "A98"]
[PlyCount "52"]
[EventDate "1998.??.??"]
[EventType "tourn (corr)"]
[EventRounds "14"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 f5 2. g3 Nf6 3. Bg2 e6 4. c4 Be7 5. Nf3 0-0 6. 0-0 d6 7. Nc3 Qe8 8. Qc2 Qh5 9. Bg5 Nc6 10. Rad1 a6 11. Bf4 h6 12. h3 g5 13. Be3 e5 14. dxe5 dxe5 15. Nd5 Bd6 16. Nxf6+ Rxf6 17. c5 Bf8 18. h4 f4 19. hxg5 hxg5 20. Bc1 Bf5 21. Qb3+ Kh7 22. e4 Be6 23. Qxb7 Nd4 24. Nxd4 exd4 25. Qxa8 Rh6 26. Rfe1 Bc4 0-1

[Event "W-ch H GT39 corr"]
[Site "ICCF corr"]
[Date "1998.??.??"]
[Round "?"]
[White "Usbeck, Karl Heinz"]
[Black "Ketzer, Jan Willem"]
[Result "1/2-1/2"]
[ECO "B85"]
[PlyCount "53"]
[EventDate "1998.??.??"]
[EventType "tourn (corr)"]
[EventRounds "14"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e6 6. Be2 a6 7. 0-0 Be7 8. f4 0-0 9. Be3 Qc7 10. Kh1 Nc6 11. Qe1 Nxd4 12. Bxd4 b5 13. a3 Bb7 14. Qg3 Bc6 15. Rae1 Qb7 16. Bd3 a5 17. Qh3 g6 18. e5 Nh5 19. Be2 dxe5 20. fxe5 b4 21. axb4 axb4 22. Nd1 Ng7 23. Ne3 Rfd8 24. Rd1 Nf5 25. Nxf5 exf5 26. Bc4 Bd5 27. Bb3 1/2-1/2

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Ambroz, Martin"]
[Black "Ketzer, Jan Willem"]
[Result "0-1"]
[ECO "D20"]
[PlyCount "46"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2024"]
[Source "ChessBase"]
[SourceDate "2023.10.19"]
[SourceVersion "1"]
[SourceVersionDate "2023.10.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 dxc4 3. Nc3 e5 4. Nf3 exd4 5. Qxd4 Qxd4 6. Nxd4 c6 7. e3 b5 8. Be2 a6 9. a3 Nf6 10. Bd2 c5 11. Ndxb5 axb5 12. Nxb5 Na6 13. Bxc4 Be7 14. f3 0-0 15. 0-0 Bd7 16. a4 Nb4 17. e4 Nc2 18. Nc7 Nxa1 19. Nxa8 Rxa8 20. Rxa1 Rxa4 21. Rc1 Bd6 22. b3 Ra3 23. Bc3 Ne8 0-1

[Event "W-ch II GT39 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Benussi, Alberto"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "D03"]
[PlyCount "73"]
[EventDate "1997.??.??"]
[EventType "tourn (corr)"]
[EventRounds "9"]
[SourceTitle "Corr 2002"]
[Source "ChessBase"]
[SourceDate "2002.05.23"]
[SourceVersion "1"]
[SourceVersionDate "2002.05.23"]
[SourceQuality "1"]

1. d4 d5 2. Nf3 Nf6 3. Bg5 Ne4 4. Bf4 Bf5 5. Nbd2 c6 6. e3 e6 7. Nxe4 Bxe4 8. Bd3 Nd7 9. Bxe4 dxe4 10. Nd2 f5 11. 0-0 Be7 12. c3 c5 13. f3 cxd4 14. exd4 Qb6 15. fxe4 0-0 16. exf5 Rxf5 17. Qa4 Qb5 18. Qb3 Qc6 19. Rae1 Rf6 20. Ne4 Rg6 21. Bg3 Rf8 22. Rxf8+ Nxf8 23. c4 b6 24. d5 exd5 25. cxd5 Bc5+ 26. Kh1 Qd7 27. d6+ Ne6 28. Bh4 Kh8 29. Qd5 h6 30. Nf6 gxf6 31. Rxe6 Bxd6 32. Rxd6 Qc7 33. Rd8+ Kh7 34. Rd7+ Qxd7 35. Qxd7+ Kg8 36. Qxa7 f5 37. Qe7 1-0

[Event "W-ch II GT39 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Bistry, Jaromir"]
[Black "Ketzer, Jan Willem"]
[Result "1/2-1/2"]
[ECO "D15"]
[PlyCount "7"]
[EventDate "1997.??.??"]
[EventType "tourn (corr)"]
[EventRounds "9"]
[SourceTitle "Corr 2002"]
[Source "ChessBase"]
[SourceDate "2002.05.23"]
[SourceVersion "1"]
[SourceVersionDate "2002.05.23"]
[SourceQuality "1"]

1. c4 Nf6 2. Nc3 c6 3. d4 d5 4. Nf3 1/2-1/2

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Jonkers, Alfons GHP"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "B12"]
[PlyCount "35"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2024"]
[Source "ChessBase"]
[SourceDate "2023.10.19"]
[SourceVersion "1"]
[SourceVersionDate "2023.10.19"]
[SourceQuality "1"]

1. d4 c6 2. e4 d5 3. e5 Bf5 4. Nf3 e6 5. Be2 c5 6. Be3 Nd7 7. c4 cxd4 8. Nxd4 Bxb1 9. Rxb1 Qa5+ 10. Bd2 Bb4 11. cxd5 Bxd2+ 12. Qxd2 Qxd5 13. 0-0 Nxe5 14. Qe3 a6 15. Rfd1 Nc4 16. Qc3 Ne5 17. Nb5 Qe4 18. Nd6+ 1-0

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Bistry, Jaromir"]
[Result "1-0"]
[ECO "A89"]
[PlyCount "43"]
[EventDate "1997.??.??"]
[EventType "tourn (corr)"]
[EventRounds "9"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 f5 2. g3 Nf6 3. Bg2 g6 4. c4 Bg7 5. Nf3 d6 6. 0-0 0-0 7. Nc3 Nc6 8. d5 Ne5 9. Nxe5 dxe5 10. c5 h6 11. Qb3 Kh8 12. e4 f4 13. Rd1 g5 14. Bf3 a6 15. c6 bxc6 16. dxc6 Qe8 17. Qc4 Qg6 18. Bg2 Nh5 19. Nd5 Qf7 20. Qc5 e6 21. Ne7 Nf6 22. Nxc8 1-0

[Event "W-ch II GT39 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Lindberg, William J"]
[Result "1-0"]
[ECO "D38"]
[PlyCount "88"]
[EventDate "1997.??.??"]
[EventType "tourn (corr)"]
[EventRounds "9"]
[SourceTitle "Corr 2002"]
[Source "ChessBase"]
[SourceDate "2002.05.23"]
[SourceVersion "1"]
[SourceVersionDate "2002.05.23"]
[SourceQuality "1"]

1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. Bg5 Bb4+ 5. Nc3 Bxc3+ 6. bxc3 0-0 7. e3 Nc6 8. Bd3 dxc4 9. Bxc4 Qd6 10. Bxf6 gxf6 11. 0-0 Qe7 12. Bd3 f5 13. Bb5 f6 14. Bxc6 bxc6 15. Qb3 Bd7 16. Rab1 Qe8 17. Qb7 e5 18. Qxc7 e4 19. Nh4 a6 20. Rb7 Rf7 21. Rfb1 Be6 22. Qg3+ Kf8 23. Rb8 Rxb8 24. Rxb8 Bc8 25. Nxf5 Qd7 26. Nd6 Ke7 27. Rxc8 Qxd6 28. Re8+ Kd7 29. Rd8+ Kxd8 30. Qxd6+ Rd7 31. Qxc6 Ke7 32. Qxe4+ Kd6 33. c4 Kc7 34. Qf4+ Kb7 35. Qxf6 Ka7 36. g4 a5 37. Qf5 Rb7 38. Qxa5+ Kb8 39. Qb5 Rxb5 40. cxb5 Kb7 41. f4 Kb6 42. f5 Kc7 43. f6 Kd6 44. b6 Ke6 1-0

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1997.??.??"]
[Round "?"]
[White "Robertshaw, Andrew M"]
[Black "Ketzer, Jan Willem"]
[Result "1/2-1/2"]
[ECO "B21"]
[PlyCount "93"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2024"]
[Source "ChessBase"]
[SourceDate "2023.10.19"]
[SourceVersion "1"]
[SourceVersionDate "2023.10.19"]
[SourceQuality "1"]

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 Nc6 5. Nf3 e6 6. Bc4 Qc7 7. Nb5 Qb8 8. Bg5 h6 9. Bd2 Nf6 10. Qe2 a6 11. Nc3 Bc5 12. Be3 Bxe3 13. Qxe3 0-0 14. 0-0 b5 15. Bd3 d6 16. Bc2 Qc7 17. Rac1 Ng4 18. Qf4 Nce5 19. Bb3 Qb6 20. Nxe5 Nxe5 21. Rfd1 Bb7 22. Rc2 Rfd8 23. Rcd2 Rac8 24. Rd4 Nc4 25. Bxc4 bxc4 26. Qd2 Rc6 27. Qe2 Qc5 28. h3 e5 29. Rd5 Qb6 30. R5d2 Rc7 31. Qg4 a5 32. Kf1 Qb4 33. a3 Qb6 34. Qe2 Kh8 35. Nd5 Bxd5 36. Rxd5 Rc6 37. a4 Rb8 38. Rb5 Qc7 39. Qd2 Rxb5 40. axb5 Rc5 41. b6 Qxb6 42. Qxd6 Qxd6 43. Rxd6 Rb5 44. Rd2 Kh7 45. Ke2 Rb3 46. Kd1 a4 47. Kc2 1/2-1/2

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1996.??.??"]
[Round "?"]
[White "Geilen, Peter"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "D12"]
[PlyCount "57"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 c6 2. c4 d5 3. Nf3 Nf6 4. e3 Bf5 5. cxd5 cxd5 6. Nc3 e6 7. Ne5 Nbd7 8. g4 Be4 9. f3 Bb4 10. Nxd7 Nxd7 11. fxe4 Bxc3+ 12. bxc3 Qh4+ 13. Kd2 dxe4 14. Ba3 0-0-0 15. h3 Ne5 16. Be2 Qf2 17. Kc2 Nc4 18. Bc1 Nxe3+ 19. Bxe3 Qxe3 20. Qd2 Qxd2+ 21. Kxd2 h5 22. g5 f5 23. Bc4 Kd7 24. h4 Rc8 25. Bb3 f4 26. Rae1 e3+ 27. Kd3 Rhf8 28. c4 Ke7 29. Ke4 1-0

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1996.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Schwerdtfeger, Hans Georg"]
[Result "1-0"]
[ECO "D18"]
[PlyCount "89"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. a4 a5 6. e3 Bf5 7. Bxc4 e6 8. 0-0 Bb4 9. Qe2 0-0 10. Bd3 Bxd3 11. Qxd3 Nbd7 12. b3 Bd6 13. Ba3 Bxa3 14. Rxa3 c5 15. Nb5 Nb6 16. e4 cxd4 17. e5 Ng4 18. Qe4 h5 19. h3 Qd5 20. Qxd5 Nxd5 21. hxg4 hxg4 22. Nfxd4 Nf4 23. Re1 Rac8 24. Nd6 Rc7 25. N4b5 Rd7 26. Re4 Nd5 27. Rxg4 f6 28. exf6 Nxf6 29. Rd4 b6 30. Ra2 Re8 31. Nxe8 Rf7 32. Nxf6+ Rxf6 33. Re2 g5 34. Rg4 Rg6 35. Re5 Rf6 36. Rgxg5+ Kf7 37. Nd6+ Ke7 38. Nc8+ Kd7 39. Nxb6+ Kc7 40. Nc4 Rh6 41. Rc5+ Kd7 42. Rxa5 Rh4 43. Rg7+ Kc6 44. Ne5+ Kd6 45. Rd7# 1-0

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1996.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Wolff, Thomas"]
[Result "1/2-1/2"]
[ECO "E12"]
[PlyCount "53"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. a3 Bb7 5. Nc3 d5 6. cxd5 Nxd5 7. Qc2 c5 8. e3 Nxc3 9. bxc3 Nc6 10. Bd3 cxd4 11. cxd4 Rc8 12. Qb1 Na5 13. Bb5+ Nc6 14. 0-0 Bd6 15. Bb2 0-0 16. Bd3 h6 17. Rc1 Qe7 18. Bh7+ Kh8 19. Be4 f5 20. Bd3 Na5 21. Rxc8 Rxc8 22. Qd1 Nc4 23. Bxc4 Rxc4 24. Ne5 Bxe5 25. dxe5 Qg5 26. g3 Qe7 27. Qd6 1/2-1/2

[Event "W-ch H GT35 corr"]
[Site "ICCF corr"]
[Date "1996.??.??"]
[Round "?"]
[White "Madsen, Flemming Lind"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "B18"]
[PlyCount "81"]
[EventDate "1996.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Bf5 5. Ng3 Bg6 6. Nf3 Nd7 7. Bd3 Bxd3 8. Qxd3 e6 9. 0-0 Ngf6 10. Bf4 Be7 11. c4 0-0 12. Rfe1 Qb6 13. Bd2 Rfd8 14. b4 Nf8 15. Nf5 Ng6 16. Nxe7+ Nxe7 17. a4 Nf5 18. a5 Qc7 19. Bg5 Qd6 20. c5 Qc7 21. Bxf6 gxf6 22. Re4 Rd5 23. Rc1 Kh8 24. a6 b6 25. Nh4 Rg8 26. Qf3 Rg5 27. Rf4 Nxh4 28. Rxh4 Rg6 29. Rf4 f5 30. Qe3 bxc5 31. bxc5 Qc8 32. Ra1 Qb8 33. Qc1 Qd8 34. Rb1 Rxd4 35. Rxd4 Qxd4 36. Rb7 e5 37. Rxa7 Qd5 38. g3 f4 39. Rb7 fxg3 40. hxg3 Qd4 41. Qe3 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Hernandez Munoz, Juan Enrique"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "B49"]
[PlyCount "71"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Nc3 Nc6 6. Be3 Qc7 7. Be2 Nf6 8. 0-0 Bb4 9. Na4 0-0 10. Nxc6 dxc6 11. c4 Nxe4 12. c5 Qe5 13. Bd4 Qg5 14. Qc2 Nf6 15. Nb6 e5 16. Be3 Qg6 17. Qxg6 fxg6 18. Nxa8 Ng4 19. Bc4+ Kh8 20. Rad1 Bf5 21. Nc7 Nxe3 22. fxe3 Bxc5 23. Rfe1 Bb4 24. Rf1 Bc5 25. Ne6 Bxe3+ 26. Kh1 Rb8 27. Rd8+ Rxd8 28. Nxd8 b5 29. Nf7+ Kg8 30. Nh6+ Kh8 31. Nxf5 gxf5 32. Rxf5 g6 33. Rxe5 Bd4 34. Re8+ Kg7 35. Be2 Bxb2 36. Rc8 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Jensen, J."]
[Black "Ketzer, Jan Willem"]
[Result "1/2-1/2"]
[ECO "E91"]
[PlyCount "49"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[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 Bg7 4. e4 0-0 5. e5 Ne8 6. Nf3 d6 7. Bf4 Nd7 8. Be2 c5 9. exd6 Nxd6 10. Nd5 cxd4 11. Bxd6 exd6 12. Nxd4 Nb6 13. Ne3 d5 14. c5 Nc4 15. 0-0 Nxb2 16. Qd2 Nc4 17. Nxc4 dxc4 18. Rad1 Bd7 19. Bxc4 Ba4 20. Nb3 Qh4 21. Qb4 Bc6 22. a3 Qg5 23. f3 Rfe8 24. Rde1 Rxe1 25. Rxe1 1/2-1/2

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Agostini, Valerio"]
[Result "1/2-1/2"]
[ECO "E62"]
[PlyCount "59"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 0-0 5. Bg2 d6 6. 0-0 c6 7. Nc3 Qa5 8. h3 e5 9. e4 exd4 10. Nxd4 Qc5 11. Qd3 Nbd7 12. Nb3 Qb4 13. Rd1 Ne8 14. Nd2 Ne5 15. Qc2 f5 16. Qb3 a5 17. exf5 Bxf5 18. f4 Nd3 19. Nde4 Bxe4 20. Nxe4 Qxb3 21. axb3 Nxc1 22. Raxc1 Bxb2 23. Rc2 Ba3 24. Ra2 Bb4 25. Bf3 Nf6 26. Nxf6+ Rxf6 27. Kg2 Re6 28. Re2 Rxe2+ 29. Bxe2 Re8 30. Kf3 1/2-1/2

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Bartl, Stanislav"]
[Result "1-0"]
[ECO "D52"]
[PlyCount "73"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. e3 c6 6. Nf3 Qa5 7. Nd2 Bb4 8. Qc2 0-0 9. Be2 dxc4 10. Bxf6 Nxf6 11. Nxc4 Bxc3+ 12. bxc3 Qc7 13. 0-0 b5 14. Ne5 a6 15. c4 c5 16. cxb5 axb5 17. Bxb5 Bb7 18. Qxc5 Qxc5 19. dxc5 Bd5 20. a4 Ne4 21. Nd7 Rfd8 22. c6 Rac8 23. Rfc1 Rc7 24. f3 Nd6 25. e4 Nxb5 26. exd5 exd5 27. axb5 d4 28. b6 Rxc6 29. Rxc6 h5 30. b7 Rxd7 31. b8Q+ Kh7 32. Ra8 f6 33. Qe8 Rd5 34. Qg8+ Kh6 35. Qxd5 d3 36. Rh8+ Kg6 37. Qxh5# 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Chranowski, Rick"]
[Result "1-0"]
[ECO "A40"]
[PlyCount "47"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 b6 2. Bg5 Bb7 3. Nd2 f5 4. Ngf3 h6 5. Bf4 Nf6 6. e3 e6 7. Ne5 g5 8. Be2 g4 9. f3 Nh5 10. 0-0 Nxf4 11. exf4 h5 12. Ng6 Rg8 13. Nxf8 Rxf8 14. c3 Nc6 15. Bd3 Qf6 16. fxg4 hxg4 17. Qe2 0-0-0 18. Bb5 Ne7 19. Ba6 Rh8 20. Bxb7+ Kxb7 21. a4 Rxh2 22. Kxh2 Qh6+ 23. Kg1 g3 24. Qf3+ 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Heinrich, Werner"]
[Result "1/2-1/2"]
[ECO "D56"]
[PlyCount "89"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. e3 0-0 6. Nf3 h6 7. Bh4 Ne4 8. Bxe7 Qxe7 9. Nxe4 dxe4 10. Nd2 e5 11. d5 f5 12. Be2 c6 13. 0-0 Rd8 14. Qc1 Qc7 15. Rd1 b6 16. Qc3 cxd5 17. cxd5 Qxc3 18. bxc3 Nd7 19. Rab1 Bb7 20. c4 g6 21. a4 Nc5 22. a5 bxa5 23. Rb5 Rac8 24. Rxa5 a6 25. Rb1 Rd7 26. f3 Rg7 27. fxe4 Nxe4 28. Nxe4 fxe4 29. d6 h5 30. c5 Kf8 31. Rb6 Rd7 32. Bxa6 Bxa6 33. Rbxa6 Kf7 34. Kf2 Rb8 35. Ra2 Rc8 36. R6a5 Ke6 37. Rd2 Rc6 38. g4 hxg4 39. Kg3 Kf5 40. Rb5 Rc8 41. Rd1 Rh8 42. c6 Rdh7 43. Rf1+ Ke6 44. d7 Rh3+ 45. Kxg4 1/2-1/2

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Hinz, Lothar"]
[Result "1-0"]
[ECO "A40"]
[PlyCount "59"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 e5 2. dxe5 Nc6 3. f4 f6 4. exf6 Nxf6 5. c3 Bc5 6. b4 Bb6 7. e3 Qe7 8. Be2 Bxe3 9. h3 0-0 10. g3 Kh8 11. Nf3 Nh5 12. Bxe3 Qxe3 13. Rg1 d5 14. Qd2 Qxd2+ 15. Nbxd2 Bxh3 16. Ng5 Nxf4 17. gxf4 Rxf4 18. Nxh3 Rh4 19. Nf2 Re8 20. a4 d4 21. b5 dxc3 22. bxc6 cxd2+ 23. Kxd2 bxc6 24. Bf3 Rf4 25. Ra3 Re5 26. Rb3 h6 27. Nd3 Rxf3 28. Rb8+ Kh7 29. Nxe5 Rf4 30. Ng6 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Kiefer, Markus"]
[Result "0-1"]
[ECO "D11"]
[PlyCount "48"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Bg5 Ne4 5. e3 Nxg5 6. Nxg5 e5 7. Nf3 Bb4+ 8. Nbd2 e4 9. a3 Bd6 10. c5 exf3 11. cxd6 fxg2 12. Bxg2 0-0 13. Bf3 Qxd6 14. Qc2 Re8 15. 0-0-0 Qf6 16. Rdg1 a5 17. h4 Bf5 18. Qc3 b5 19. h5 b4 20. Qb3 bxa3 21. bxa3 Nd7 22. h6 Nc5 23. dxc5 Qa1+ 24. Nb1 Rab8 0-1

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Ram, Herman"]
[Result "1-0"]
[ECO "D11"]
[PlyCount "47"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. d4 d5 2. c4 dxc4 3. Nf3 Nf6 4. e3 b5 5. a4 c6 6. axb5 cxb5 7. b3 e6 8. bxc4 bxc4 9. Bxc4 Bb4+ 10. Bd2 Bxd2+ 11. Nbxd2 0-0 12. 0-0 Nc6 13. Rb1 Qc7 14. h3 Bb7 15. Bd3 Rfd8 16. Qa4 Rd5 17. Rfc1 Qa5 18. Qc4 Qc7 19. Rxb7 Qxb7 20. Qxc6 Qxc6 21. Rxc6 a5 22. Nc4 Nd7 23. Rc7 Nf6 24. Nb6 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Lehmann, Horst"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "C02"]
[PlyCount "63"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[SourceTitle "Corr 2000"]
[Source "ChessBase"]
[SourceDate "2000.04.19"]
[SourceVersion "1"]
[SourceVersionDate "2000.04.19"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. e5 c5 4. Nf3 c4 5. b3 cxb3 6. axb3 Nc6 7. Bd3 f6 8. 0-0 a6 9. Na3 Bb4 10. Bd2 fxe5 11. dxe5 Bd7 12. c3 Bc5 13. Qc2 g6 14. Qb2 Nge7 15. b4 Bb6 16. c4 0-0 17. cxd5 Nxd5 18. Be4 Rc8 19. Nc4 Nd4 20. Nd6 Rxf3 21. gxf3 Bb5 22. Nxc8 Qxc8 23. Rfd1 Ne2+ 24. Kh1 Bd4 25. Qb3 Bxa1 26. Bxd5 Nd4 27. Bxe6+ Qxe6 28. Qxe6+ Nxe6 29. Rxa1 Bc6 30. Kg2 Kf7 31. Be3 g5 32. Kg3 1-0

[Event "W-ch H GT31 corr"]
[Site "ICCF corr"]
[Date "1995.??.??"]
[Round "?"]
[White "Ruhle, Ernst Olav"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "E69"]
[PlyCount "49"]
[EventDate "1995.??.??"]
[EventType "tourn (corr)"]
[EventRounds "11"]
[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 Bg7 4. Nf3 d6 5. g3 0-0 6. Bg2 Nbd7 7. 0-0 e5 8. e4 c6 9. h3 Re8 10. Re1 a5 11. Rb1 Qc7 12. b3 h6 13. Be3 exd4 14. Nxd4 Nc5 15. Bf4 g5 16. Bc1 Bd7 17. f4 g4 18. h4 Nh5 19. Kh2 Nf6 20. a3 h5 21. Bb2 Qb6 22. Ba1 Re7 23. b4 axb4 24. axb4 Qxb4 25. Rxb4 1-0

[Event "NED theme01 corr"]
[Site "Netherlands"]
[Date "1986.??.??"]
[Round "?"]
[White "Janssen, Helmut"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "A56"]
[PlyCount "99"]
[EventDate "1986.??.??"]
[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. d4 Nf6 2. c4 c5 3. d5 Ne4 4. Qd3 Qa5+ 5. Nc3 Nxc3 6. Bd2 e5 7. Qxc3 Qc7 8. g3 d6 9. Bh3 Na6 10. f4 Be7 11. Bxc8 Rxc8 12. e4 Bf6 13. f5 Qd7 14. h4 b5 15. g4 b4 16. Qg3 h6 17. Nf3 Qa4 18. b3 Qa3 19. Bc1 Qa5 20. g5 hxg5 21. Bxg5 Qd8 22. Ke2 Kd7 23. h5 Nc7 24. h6 Qg8 25. Rag1 Ne8 26. Bxf6 Nxf6 27. hxg7 Rh7 28. Ke3 Nh5 29. Rxh5 Rxh5 30. f6 Qh7 31. Qg4+ Kc7 32. Qxc8+ Kxc8 33. g8Q+ Qxg8 34. Rxg8+ Kd7 35. Ra8 Rh6 36. a4 a5 37. Ra7+ Ke8 38. Rxa5 Rxf6 39. Rb5 Rh6 40. Rb6 f5 41. exf5 Kd7 42. Nxe5+ Kc7 43. a5 Rh3+ 44. Nf3 Rh1 45. Rc6+ Kd7 46. f6 Ra1 47. Rc7+ Ke8 48. f7+ Kf8 49. a6 Ra3 50. Ng5 1-0

[Event "NED theme01 corr"]
[Site "Netherlands"]
[Date "1986.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Janssen, Helmut"]
[Result "0-1"]
[ECO "A56"]
[PlyCount "88"]
[EventDate "1986.??.??"]
[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. d4 Nf6 2. c4 c5 3. d5 Ne4 4. Qc2 Qa5+ 5. Nd2 Nd6 6. b3 f5 7. Bb2 e6 8. Bc3 Qd8 9. e4 Qe7 10. g3 fxe4 11. 0-0-0 e3 12. fxe3 b5 13. Bg2 b4 14. Bb2 Bb7 15. Ne2 Nf7 16. Nf4 Nd8 17. Bf3 d6 18. Bh5+ Kd7 19. Bg4 Kc7 20. e4 e5 21. Ne6+ Nxe6 22. dxe6 Nc6 23. Rhf1 Nd8 24. Rf2 Nxe6 25. Rdf1 Nd8 26. Nf3 h5 27. Bf5 g5 28. Rd1 Kb6 29. a3 a5 30. Rfd2 Qf6 31. Rd3 Nf7 32. Qd2 bxa3 33. Bxa3 g4 34. h4 gxf3 35. Qf2 Nh6 36. Rxf3 Nxf5 37. Rxf5 Qh6+ 38. Kb2 Be7 39. Qe2 Rhf8 40. Kc3 Qg6 41. Rxf8 Rxf8 42. Qe3 Bxe4 43. b4 axb4+ 44. Bxb4 Rf3 0-1

[Event "NED theme01 corr"]
[Site "Netherlands"]
[Date "1986.??.??"]
[Round "?"]
[White "Ketzer, Jan Willem"]
[Black "Weegenaar, Bertrand W"]
[Result "0-1"]
[ECO "A56"]
[PlyCount "40"]
[EventDate "1986.??.??"]
[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. d4 Nf6 2. c4 c5 3. d5 Ne4 4. Qc2 Qa5+ 5. Nd2 Nxd2 6. Bxd2 Qc7 7. Nf3 d6 8. Bc3 e5 9. dxe6 Bxe6 10. Qe4 Qc6 11. Qe3 Na6 12. a3 Nc7 13. Ne5 dxe5 14. Bxe5 Rd8 15. Rc1 Rd7 16. f3 Re7 17. Qd3 Bxc4 18. Qe3 Nd5 19. Qe4 Bb3 20. e3 f6 0-1

[Event "NED theme01 corr"]
[Site "Netherlands"]
[Date "1986.??.??"]
[Round "?"]
[White "Weegenaar, Bertrand W"]
[Black "Ketzer, Jan Willem"]
[Result "1-0"]
[ECO "A56"]
[PlyCount "45"]
[EventDate "1986.??.??"]
[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. d4 Nf6 2. c4 c5 3. d5 Ne4 4. Qc2 Qa5+ 5. Nd2 Nd6 6. e4 g6 7. b4 Qxb4 8. Rb1 Qa5 9. Bb2 Rg8 10. Bd3 f5 11. Bc3 Qc7 12. e5 e6 13. exd6 Bxd6 14. Ndf3 b6 15. h4 h6 16. h5 Na6 17. hxg6 Rxg6 18. Bxf5 Rxg2 19. Rxh6 Bg3 20. Bg6+ Ke7 21. Rh7+ Kd6 22. fxg3 exd5 23. Be5+ 1-0

