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Invariant approximations in CAT(0) spaces. (English) Zbl 1167.47042
Summary: Some common fixed point and invariant approximation results for CAT(0) spaces are obtained. Our results improve and extend some results of N. Shahzad and J. Markin [J. Math. Anal. Appl. 337, No. 2, 1457–1464 (2008; Zbl 1137.47043)] and of S. Dhompongsa, A. Kaewkhao and B. Panyanak [J. Math. Anal. Appl. 312, No. 2, 478–487 (2005; Zbl 1086.47019)].

##### MSC:
 47H10 Fixed-point theorems 41A65 Abstract approximation theory (approximation in normed linear spaces and other abstract spaces) 54H25 Fixed-point and coincidence theorems (topological aspects) 58C30 Fixed-point theorems on manifolds 47H09 Contraction-type mappings, nonexpansive mappings, $$A$$-proper mappings, etc.
##### Keywords:
invariant approximation; nonexpansive mapping; CAT(0) space
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##### References:
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