(A34) Rubinstein
1. c4 c5 2. Nc3 Nf6 3. g3 d5 4. cxd5 Nxd5
(A34) Three Knights
1. c4 c5 2. Nc3 Nf6 3. Nf3 d5 4. cxd5 Nxd5
(A34) Keres
1. c4 c5 2. Nc3 Nf6 3. Nf3 d5 4. cxd5 Nxd5 5. g3 Nc6 6. Bg2 e6 7. O-O Be7