[Event "IBM"]
[Site "Amsterdam"]
[Date "1968.??.??"]
[Round "6"]
[White "Kotov, Alexander"]
[Black "Jongsma, Alexander"]
[Result "1-0"]

1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. e3 Bg7 5. Qb3 c6 6. Nf3 O-O 7. Bd2 e6 8. Bd3 b6 9. a4 c5 10. dxc5 bxc5 11. O-O Nc6 12. cxd5 exd5 13. Bb5 Rb8 14. Qa3 Nb4 15. Rac1 Qd6 16. Be2 a5 17. Rfd1 Bf5 18. Nb5 Qe7 19. Bf1 Ne4 20. Bc3 Rfe8 21. Bxg7 Kxg7 22. Nc3 Nf6 23. Bb5 Red8 24. b3 Rb6 25. Qb2 Kg8 26. Qe2 Re6 27. Rd2 d4 28. Qd1 d3 29. Bc4 Red6 30. Ng5 Nfd5 31. Nxd5 Nxd5 32. h4 h6 33. e4 hxg5 34. Bxd5 Bxe4 35. Bxe4 Qxe4 36. hxg5 Rd5 37. Rc4 Qe5 38. Rg4 Kg7 39. Rg3 Qc3 40. Re3 Rxg5 41. Rdxd3 Rxd3 42. Rxd3 Qe5 43. Re3 Qd5 44. Qa1+ Kh7 45. Rh3+ Rh5 46. Rf3 Rf5 47. Rg3 Rg5 48. Rxg5 Qxg5 49. Qc3 Qd5 50. f3 Kg8 51. Kf2 Qd1 52. Qxc5 Qd2+ 53. Kg3 f5 54. Qe7 Qd4 55. Qe8+ Kg7 56. Qe7+ Kg8 57. Qe6+ Kg7 58. Qc4 Qd2 59. Qf4 Qe1+ 60. Kh2 Kh7 61. Qg3 Qd2 62. Qh4+ Kg7 63. Qe7+ Kg8 64. Qf6 Kh7 65. Kh3 Qd1 66. Qe7+ Kh6 67. Qe5 Qd8 68. Qf4+ Kg7 69. b4 g5 70. Qe5+ Kg6 71. bxa5 Qd7 72. Kh2 Qh7+ 73. Kg1 Qa7+ 74. Kf1 Qd7 75. Ke2 Qc6 76. Kd3 Qc1 77. Qe6+ Kg7 78. a6 Qd1+ 79. Kc3 Qa1+ 80. Kb4 Qb2+ 81. Kc5 Qc3+ 82. Kd6 Qb4+ 83. Kc7 Qa5+ 84. Kb7 Qb4+ 85. Qb6 Qxa4 86. a7 1-0