Morteza Ayobian

1. Introduction In 1974, Ćirić [ 1 ] proved a fixed point (fp) result for a novel class of contractive mappings, which is called quasi-contraction mapping. In fact, he showed that quasi-contraction is a real generalization of some well-known linear contractions, and his result was an expansion of the Banach contraction principle. Then, he proved the existence and uniqueness of fp for T -orbitally single-valued mappings and F -orbitally multi-valued mappings in complete metric spaces.

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