ECO D39: Queen's Gambit Declined

ECO D39 is part of volume D — Closed & Semi-Closed Games. The Lichess chess-openings dataset files one named line under it. It is Queen's Gambit Declined: Ragozin Defense, Vienna Variation: 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Bb4 5. Bg5 dxc4.

That position has come up in 146,821 Lichess games between players rated 1600 to 2500: White won 51.2%, 5.3% were drawn and Black won 43.5%.