ECO E51
3 named openings and variations are classified as E51. ECO (Encyclopaedia of Chess Openings) codes group openings from A00 to E99 by their opening moves.
- Nimzo-Indian Defense: Normal Variation, Ragozin VariationE511. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5
- Nimzo-Indian Defense: Normal Variation, Sämisch DeferredE511. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5 6. a3
- Nimzo-Indian Defense: Ragozin VariationE511. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Bd3 d5 6. Nf3 Nc6 7. O-O dxc4