[Event "Interzonal-06"]
[Site "Amsterdam"]
[Date "1964.06.16"]
[Round "20"]
[White "Ivkov, Borislav"]
[Black "Spassky, Boris Vasilievich"]
[Result "1/2-1/2"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 Bc5 4. O-O Nd4 5. Nxd4 Bxd4 6. c3 Bb6 7. d4 c6 8. Bc4 d6 9. dxe5 dxe5 10. Qxd8+ Bxd8 11. Be3 Nf6 12. f3 Bb6 13. Kf2 Ke7 14. Nd2 Bxe3+ 15. Kxe3 Be6 16. Rfd1 Rhd8 17. Bxe6 Kxe6 18. Nb3 b6 19. a4 a5 20. Rd2 Rd7 21. Rad1 Rad8 22. g3 Rxd2 23. Rxd2 Rxd2 24. Nxd2 Nd7 25. Nc4 f6 26. b4 axb4 27. cxb4 b5 28. axb5 cxb5 29. Na3 Nb8 30. Kd3 Na6 31. Ke3 Nc7 1/2-1/2