411 REFERENCE · Wikibooks
Chess Opening Theory/1. e4/1...e5/2. Nc3/2...Nf6/3. Bc4/3...Bb4
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Vienna Game, Stanley Variation, Reversed Spanish
Black has attacked the knight on c3 to grab it later. The position stays pretty equal, but both sides should play more careful.
Common move is 4. f4 to bring out the Vienna Gambit before it gets too late.
The position looks like Ruy Lopez but in second hand.