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Almost fixed point theorems

Author: Adam Idzik
Journal: Proc. Amer. Math. Soc. 104 (1988), 779-784
MSC: Primary 47H10; Secondary 54H25, 55M20
MathSciNet review: 964857
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Abstract: A closed cover version of Hazewinkel and van de Vel's theorem on the existence of $ \gamma $-almost fixed points for set-valued functions and for real Hausdorff topological vector spaces is proved. Generalizations of well-known fixed point theorems of the Schauder-Tychonoff type are presented.

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Keywords: Fixed point, convexoid cover, Čech homology functor, almost convex set
Article copyright: © Copyright 1988 American Mathematical Society

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