1.Be5+Nc7+
2.Kb6Bd8
3.Bd7!
No other waiting move wins, eg. 3.Bh3? Ka8 4.Bg2+ Nd5+! 5.Ka6 Bc7 6.Bxc7 is stalemate - White must circumscribe d5
3...Ka8
4.Bc6+Kb8
5.Bb7!any
6.Bxc7#
Goldberg (1931)