The game was played in the 1974/5 Hastings Masters between GM Rafael Vaganian from Armenia and GM Albin Planinec from Slovenia.Answer: 22…Qc7+! 0-1 A classic deflection move, after 23.Qxc7 Nb3 is mate!
Reference: 'Littlewoods Choice' ChessMoves Jan/Feb 2009, p.14.