Nimzo-Indian, 4.e3, Bronstein (Byrne) Variation 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 b6 5. Ne2 Ba6
In each game under Location you see masterchessopen.com but it's not a valid website, so please don't use it. Claus Gamborg, Jan. 2023