D51Black13 book lines continue
Modern Variation, Knight Defense
Queen's Gambit Declined1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. e3 c6
Also known as QGD: 4.Bg5 Nbd7 5.e3 c6, Queen's Gambit Declined: Modern, Knight Defense, 4. Bg5 Nbd7 5. e3 c6, Queen's Gambit Declined, Modern.