[Event "IBM"]
[Site "Amsterdam"]
[Date "1969.??.??"]
[Round "9"]
[White "Donner, Jan Hein"]
[Black "Ivkov, Borislav"]
[Result "1/2-1/2"]

1. d4 g6 2. e4 Bg7 3. Nc3 d6 4. f4 a6 5. Nf3 b5 6. Bd3 Bb7 7. Be3 Nd7 8. a4 b4 9. Ne2 Ngf6 10. Nd2 c5 11. c3 bxc3 12. bxc3 cxd4 13. cxd4 Qa5 14. O-O Ng4 15. Rf3 Nxe3 16. Rxe3 Qb6 17. Rb1 Qa7 18. Kh1 Nf6 19. h3 O-O 20. Bc2 Rac8 21. Reb3 Bc6 22. Rc3 Bd7 23. Rxc8 Rxc8 24. Bd3 Bc6 25. Qb3 Nd7 26. Nf3 Rb8 27. Qa2 Rxb1+ 28. Bxb1 Qb7 29. Bd3 e6 30. Nc3 Nf6 31. Qc4 a5 32. Nd2 Nh5 33. Ne2 d5 34. Qc2 dxe4 35. Bxe4 Bxe4 36. Nxe4 Bxd4 37. Nxd4 Qxe4 38. Qxe4 Ng3+ 39. Kh2 Nxe4 40. Nb3 Nc3 41. Nxa5 Nxa4 42. Kg3 f6 43. Kf3 Kf7 44. Nc4 Nc5 45. Ke3 Ke7 46. Kd4 Nb7 47. Nd2 Nd6 48. Nf3 Nf5+ 49. Kd3 Ng3 50. Ke3 Kd6 51. Kf2 Ne4+ 52. Ke3 Kd5 53. Nd4 Ng3 54. Nb5 Kc5 55. Nc7 Nf5+ 56. Ke4 Kd6 57. Nb5+ Kc6 58. Nc3 Kc5 59. Kd3 Nd6 60. Ne2 h6 61. Nc3 Kb4 62. Ne2 Nb5 63. h4 Kc5 64. g4 Kd5 65. Ke3 Nd6 66. Nc3+ Kc4 67. Ne2 h5 68. g5 Nf5+ 69. Ke4 Nd6+ 70. Ke3 fxg5 71. hxg5 Kd5 72. Nc3+ Kc4 73. Ne2 Kd5 74. Nc3+ Kc5 75. Ne2 Kc4 76. Ng1 Kd5 77. Nf3 Nf5+ 78. Kd3 h4 79. Ne5 h3 80. Ng4 Nh4 81. Ke3 Ng2+ 82. Kf3 Kd4 83. Kg3 Ke4 84. Nf2+ Kf5 85. Nxh3 Ne3 86. Nf2 Nf1+ 87. Kf3 Nd2+ 88. Ke3 1/2-1/2