Kantorovich’s Fixed Point Theorem in Metric Spaces and Coincidence Points

Existence and uniqueness theorems are obtained for a fixed point of a mapping from a complete metric space to itself. These theorems generalize the theorems of L. V. Kantorovich for smooth mappings of Banach spaces. The results are extended to the coincidence points of both ordinary and set-valued mappings acting in metric spaces. © 2019, Pleiades Publishing, Ltd.