411 REFERENCE · Wikibooks
Chess Opening Theory/1. d4/1...Nc6/2. d5/2...Ne5/3. f4/3...Ng6/4. e4
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Mikenas Defence
4. e4
White has taken the center. Black should play /4...e5/ or /4...e6/.