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Proceedings of the American Mathematical Society

Published by the American Mathematical Society since 1950, Proceedings of the American Mathematical Society is devoted to shorter research articles in all areas of pure and applied mathematics.

ISSN 1088-6826 (online) ISSN 0002-9939 (print)

The 2020 MCQ for Proceedings of the American Mathematical Society is 0.85.

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A Leray-Schauder type theorem for approximable maps
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by H. Ben-El-Mechaiekh and A. Idzik PDF
Proc. Amer. Math. Soc. 122 (1994), 105-109 Request permission

Abstract:

We present an elementary proof of a Leray-Schauder type theorem for approximable set-valued maps. Our theorem generalizes many results for convex as well as nonconvex maps. Our argument is not based on a homotopy invariance property but, quite surprisingly, on a matching theorem of Ky Fan on closed covers of convex sets.
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Additional Information
  • © Copyright 1994 American Mathematical Society
  • Journal: Proc. Amer. Math. Soc. 122 (1994), 105-109
  • MSC: Primary 54H25; Secondary 47H04, 47H10, 54C60
  • DOI: https://doi.org/10.1090/S0002-9939-1994-1212281-2
  • MathSciNet review: 1212281