OPREA, Anca, and Gabriela PETRUȘEL. 2016. “Coupled Fixed Point Theorems for Rational Type Contractions: Dedicated to Professor Ioan A. Rus on the Occasion of His 80th Anniversary”. Studia Universitatis Babeș-Bolyai Mathematica 61 (4):473-88. https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/5639.