A note on the existence of Berge and Berge-Nash equilibria

This paper deals with the problem of existence of Berge and Berge-Nash equilibria. Abalo and Kostreva have proved existence theorems of Berge and Berge-Nash equilibria for S-equi-well-posed and (S, σ)-equi-well-posed games, namely, Theorems 3.2-3.3 [Abalo, K.Y., Kostreva, M.M., 1996. Fixed Points, Nash Games and their Organization. Topological Methods in Nonlinear Analysis 8, 205-215.]. In this paper we show that the assumptions of these theorems are actually not sufficient for the existence of Berge equilibrium. We then propose a new version of these theorems.