E21 — Nimzo-Indian Defense: Three Knights Variation

ECO E21 covers Nimzo-Indian Defense: Three Knights Variation and related lines (Nimzo-Indian Defense: Three Knights Variation, Nimzo-Indian Defense: Three Knights Variation, Korchnoi Variation, Nimzo-Indian Defense: Three Knights Variation, Euwe Variation, Nimzo-Indian Defense: Three Knights Variation, Shocron Gambit). Main line 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 with variations, statistics, and the best responses.