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Gregus-type common fixed point theorems for tangential multivalued mappings of integral type in metric spaces. (English) Zbl 1215.54026
Summary: The concept of tangential for single-valued mappings is extended to multivalued mappings and used to prove the existence of a common fixed point theorem of Gregus type for four mappings satisfying a strict general contractive condition of integral type. Consequently, several known fixed point results are generalized and improved as the corresponding recent results of H. K. Pathak and N. Shahzad [Bull. Belg. Math. Soc. - Simon Stevin 16, No. 2, 277–288 (2009; Zbl 1167.54016)] and many authors.
54H25Fixed-point and coincidence theorems in topological spaces