[Event "IBM"]
[Site "Amsterdam"]
[Date "1971.07.15"]
[Round "3"]
[White "Donner, Jan Hein"]
[Black "Bobotsov, Milko Georgiev"]
[Result "1/2-1/2"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 c5 5. Bd3 O-O 6. Nf3 b6 7. O-O Bb7 8. Bd2 d6 9. Qe2 Bxc3 10. Bxc3 Ne4 11. Be1 Qe7 12. Nd2 f5 13. f3 Nxd2 14. Bxd2 e5 15. dxe5 dxe5 16. Bc3 Nc6 17. a3 Rad8 18. Bc2 g6 19. Rae1 Rd7 20. Qf2 Qf7 21. Ba4 Qxc4 22. Bxc6 Bxc6 23. Bxe5 Qe6 24. Qg3 Re8 25. Bf4 Bb5 26. Rf2 Red8 27. h4 Rd1 28. Rxd1 Rxd1+ 29. Kh2 Rd7 30. h5 Kf7 31. Be5 Ke8 32. e4 Kd8 33. Qf4 Bd3 34. exf5 Qxf5 35. Bf6+ Kc8 36. Qxf5 Bxf5 37. h6 Bd3 38. g4 Kb7 39. Kg3 b5 40. Kf4 Kc6 1/2-1/2