[Event "Vidmar Memorial-04"]
[Site "Ljubljana/Portoroz"]
[Date "1977.06.05"]
[Round "4"]
[White "Sosonko, Gennadi"]
[Black "Sigurjonsson, Gudmundur"]
[Result "1/2-1/2"]
[WhiteElo "2530"]
[BlackElo "2520"]

1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Be2 O-O 6. Nf3 e5 7. O-O Nbd7 8. Re1 c6 9. Bf1 a5 10. Rb1 Re8 11. d5 Nc5 12. b3 Qc7 13. a3 Bg4 14. h3 Bxf3 15. Qxf3 Rac8 16. Qd1 Na6 17. b4 axb4 18. axb4 c5 19. Nb5 Qe7 20. bxc5 Nxc5 21. Qc2 1/2-1/2