[Event "IBM"]
[Site "Amsterdam"]
[Date "1968.??.??"]
[Round "4"]
[White "Kotov, Alexander"]
[Black "Donner, Jan Hein"]
[Result "1/2-1/2"]
[WhiteElo ""]
[BlackElo ""]
[ECO "A15"]

1.c4 Nf6 2.Nf3 g6 3.b3 Bg7 4.Bb2 O-O 5.g3 d6 6.Bg2 e5 7.O-O Nfd7 8.d4 e4
9.Ne1 Re8 10.Nc3 f5 11.Nc2 Nf6 12.d5 Nbd7 13.Qd2 a5 14.Nb5 Nc5 15.Ne3 Bd7
16.Nd4 h5 17.Bc3 Ng4 18.Nxg4 hxg4 19.Nc2 Bxc3 20.Qxc3 Kf7 21.f3 gxf3 22.exf3 exf3
23.Rxf3 Qf6 24.Raf1 Qxc3 25.Rxc3 Re2 26.Rf2 Ne4 27.Bxe4 Rxe4 28.Rf4 Re2 29.Rf2 Re4
30.Re3 Rxe3 31.Nxe3 Re8 32.Re2 Re4 33.Kf2 f4 34.gxf4 Rxf4+ 35.Ke1 Kf6 36.Kd2 Rf3
37.Nd1 Bf5 38.Re3 Rxe3 39.Kxe3 Ke5 40.Nc3 c6 41.dxc6 bxc6 42.Ne2 1/2-1/2