AUTOMORPHISMS OF AN IRREGULAR SURFACE OF GENERAL TYPE ACTING TRIVIALLY IN COHOMOLOGY, II

Abstract

Let $S$ be a complex nonsingular minimal projective surface of general type with $q(S)=2$, and let $G$ be the group of the automorphisms of $S$ acting trivially on $H^2(S, \boldsymbol{Q})$. In this note we classify explicitly pairs $(S, G)$ with $G$ of order four.