[Event "IBM"]
[Site "Amsterdam"]
[Date "1973.??.??"]
[Round "4"]
[White "Donner, Jan Hein"]
[Black "Ribli, Zoltan"]
[Result "1-0"]
[WhiteElo "2480"]
[BlackElo "2525"]
[ECO "E66"]

1.d4 Nf6 2.c4 g6 3.g3 Bg7 4.Bg2 O-O 5.Nc3 d6 6.Nf3 Nc6 7.d5 Na5 8.b3 c5 9.Bb2 a6
10.O-O Rb8 11.Nd2 b5 12.Qc2 e5 13.Rae1 Nh5 14.e4 f5 15.exf5 gxf5 16.Ne2 f4
17.gxf4 Nxf4 18.Nxf4 Rxf4 19.cxb5 axb5 20.Ne4 Rb7 21.Bc1 Rg4 22.f4 exf4 23.Bxf4 Bd4+
24.Kh1 Rbg7 25.Bg3 Nb7 26.Bf3 R4g6 27.Bh5 Rh6 28.Nf6+ Bxf6 29.Re8+ Qxe8 30.Bxe8 Bh3
31.Rg1 b4 32.Qe4 Bd4 33.Bb5 Rf6 34.Re1 Bf5 35.Qh4 Rg4 36.Re8+ Kg7 37.Re7+ Kg8
38.Re8+ Kg7 39.Qh5 Re4 40.Qg5+  1-0

