Contractions of Kannan-type and of Chatterjea-type on fuzzy quasi-metric spaces

Abstract

We characterize the completeness of fuzzy quasi-metric spaces by means of a fixed point theorem of Kannan-type.Thus, we extend the classical characterization of metric completeness due to Subrahmanyam as well as recent resultsin the literature on the characterization of quasi-metric completeness and fuzzy metric completeness, respectively. Wealso introduce and discuss contractions of Chatterjea-type in this asymmetric context.