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A Leray-Schauder type theorem
for approximable maps: a simple proof

Authors: H. Ben-El-Mechaiekh, S. Chebbi and M. Florenzano
Journal: Proc. Amer. Math. Soc. 126 (1998), 2345-2349
MSC (1991): Primary 47H04, 47H10, 54C60
MathSciNet review: 1476117
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Abstract: We present a simple and direct proof for a Leray-Schauder type alternative for a large class of condensing or compact set-valued maps containing convex as well as nonconvex maps.

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Additional Information

H. Ben-El-Mechaiekh
Affiliation: Department of Mathematics, Brock University, St. Catharines, Ontario, Canada L2S 3A1
Address at time of publication: Department of Mathematics, The American University of Sharjah, P.O. Box 26666, Sharjah, United Arab Emirates

S. Chebbi
Affiliation: CERMSEM, Université de Paris I, 106-112 Bd de l’Hopital, 75013 Paris, France

M. Florenzano
Affiliation: CNRS-CEPREMAP, 140 rue du Chevaleret, 75013 Paris, France

Keywords: Leray-Schauder alternative, approximable set-valued maps, condensing, compact
Received by editor(s): August 12, 1996
Received by editor(s) in revised form: January 16, 1997
Communicated by: Palle E. T. Jorgensen
Article copyright: © Copyright 1998 American Mathematical Society

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