E51: Nimzo-Indian, 4.e3, Ragozin variation

E51 Sub-variants:

• Nimzo-Indian, 4.e3 e8g8, 5.Nf3 d7d5
  1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5
• Nimzo-Indian, 4.e3, Ragozin variation
  1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5 6. Bd3 Nc6 7. O-O dxc4