The Picard group of a quasi-bundle

Abstract

Quasi-bundles are morphisms from an algebraic surface onto a curve having all smooth fibres connected and pairwise isomorphic, and whose only singular fibres are multiplies of smooth curves. Let F denote de general fiber of a quasi-bundle map defined on a surface S. This paper focuses on the relationship between the divisibility properties of F in H2 (S, ℤ)/(torsion) and the torsion of H2 (S, ℤ). © 1991 Springer-Verlag.