[Event "IBM"]
[Site "Amsterdam"]
[Date "1970.07.21"]
[Round "7"]
[White "Donner, Jan Hein"]
[Black "Ree, Hans"]
[Result "1-0"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Bd3 d5 6. Nf3 b6 7. O-O Bb7 8. a3 Bd6 9. b4 dxc4 10. Bxc4 Nbd7 11. Bb2 a5 12. bxa5 Rxa5 13. Qe2 e5 14. Nb5 e4 15. Ne5 Be7 16. Bc3 Ra8 17. Bb4 Nb8 18. Qb2 Nc6 19. Nxc6 Bxc6 20. Rac1 Bxb4 21. axb4 Qd7 22. Nxc7 Ra7 23. b5 Bb7 24. Be2 Ra5 25. Rc2 Qf5 26. Rfc1 h5 27. h3 g5 28. Ra1 Rxa1+ 29. Qxa1 g4 30. h4 Bd5 31. g3 Rc8 32. Qa6 Rb8 33. Qa7 Rb7 34. Qa8+ Kg7 35. Nxd5 Qxd5 36. Rc6 Qd7 37. Bc4 Ne8 38. Kg2 Ra7 39. Qb8 Ra1 40. Qe5+ f6 41. Qxh5 1-0