Petrosian, Tigran V VS Ree, Hans 1973.??.??

[Event "IBM"]
[Site "Amsterdam"]
[Date "1973.??.??"]
[Round "7"]
[White "Petrosian, Tigran V"]
[Black "Ree, Hans"]
[Result "1/2-1/2"]

1. d4 Nf6 2. c4 g6 3. d5 Bg7 4. g3 c6 5. Bg2 Qa5+ 6. Nc3 Qb4 7. Qd3 d6 8. Kf1 cxd5 9. cxd5 Na6 10. a3 1/2-1/2