On proper holomorphic mappings between rigid polynomial domains in Cn+1

We study the behavior of the branch locus of proper holomorphic mappings between nondegenerate rigid polynomial domains in Cn+1nonnecessary pseudoconvex. In particular, we show that it depends only on the first domain. This paper generalizes [Publ. Mat. 45 (2001) 69-77] in the nonpseudoconvex case.