Remarks on Extensions of the Himmelberg Fixed Point Theorem
© H. Komiya and S. Park. 2007
Received: 30 August 2007
Accepted: 16 November 2007
Published: 13 December 2007
Recently, Jafari and Sehgal obtained an extension of the Himmelberg fixed point theorem based on the Kakutani fixed-point theorem. We give generalizations of the extension to almost convex sets instead of convex sets. We also give generalizations for a large class of better admissible multimaps instead of the Kakutani maps. Our arguments are based on the KKM principle and some of previous results due to the second author.
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