[Event "Olympiad-23"]
[Site "Buenos Aires"]
[Date "1978.11.08"]
[Round "13"]
[White "Vilela de Acuna, Jose Luis"]
[Black "Petursson, Margeir"]
[Result "1/2-1/2"]
[WhiteElo "2435"]
[BlackElo "2350"]

1. c4 c5 2. Nf3 g6 3. d4 cxd4 4. Nxd4 Bg7 5. e4 Nc6 6. Be3 Nf6 7. Nc3 O-O 8. Be2 d6 9. O-O Bd7 10. Rc1 Nxd4 11. Bxd4 Bc6 12. f3 a5 13. b3 Nd7 14. Be3 Nc5 15. Qd2 Qb6 16. Nb5 Rfc8 17. Rfd1 Qd8 18. Bf1 Qf8 19. Nc3 Be5 20. Bd3 Qd8 21. Kh1 e6 22. Qf2 Qf6 23. Ne2 g5 24. Bb1 h6 25. Bd4 b6 26. Rd2 Kf8 27. Rcd1 Ke7 28. Nc1 Rd8 29. Bxe5 Qxe5 30. Nd3 Nxd3 31. Bxd3 Qc5 32. Qg3 a4 33. Bf1 axb3 34. axb3 Ra3 35. e5 Rxb3 36. exd6+ Kd7 37. Qh3 Qe5 38. Ra2 Kc8 39. Rad2 Ra3 40. Qh5 Qf6 41. Qh3 Kd7 42. Qg3 Rda8 43. Qf2 Rb3 44. c5 b5 45. Rd4 Raa3 46. Kg1 Qe5 47. f4 Qe3 48. Qxe3 Rxe3 49. fxg5 hxg5 50. Rb1 Reb3 51. Rxb3 Rxb3 52. Rg4 Rb1 53. Rxg5 b4 54. Kf2 b3 55. Rg4 Rc1 56. Rb4 Rc2+ 57. Ke3 b2 58. Kd4 Rf2 59. Bd3 Rxg2 60. Kc3 Rg5 61. Kd4 e5+ 62. Ke3 e4 63. Bb5 1/2-1/2