Remarks on generalized quasi-equilibrium problems

Our main aim in this paper is to obtain fundamental existence theorems of quasi-equilibrium problems and generalized quasi-equilibrium problems of multivalued functions. We use a continuous selection theorem to show that the existence theorems of generalized quasi-equilibrium problems are simple consequences of the corresponding quasi-equilibrium problems. We use a generalization of Himmelberg's theorem due to the third author for not necessary locally convex topological vector spaces to prove the existence theorems of quasi-equilibrium problems for multivalued functions. (C) 2002 Elsevier Science Ltd. All rights reserved.