[Event "Hoogovens"]
[Site "Wijk aan Zee"]
[Date "1971.01.22"]
[Round "9"]
[White "Ivkov, Borislav"]
[Black "Ree, Hans"]
[Result "1/2-1/2"]
1. Nf3 g6 2. d4 Bg7 3. c4 Nf6 4. Nc3 d5 5. Qb3 dxc4 6. Qxc4 O-O 7. e4 a6 8. Bf4 b5 9. Qxc7 Qxc7 10. Bxc7 Bb7 11. e5 Nd5 12. Nxd5 Bxd5 13. Be2 Rc8 14. Ba5 Nc6 15. Bc3 b4 16. Bd2 f6 17. O-O 1/2-1/2