URS C. Fixed point theorems for a system of operator equations with applications. Stud. Univ. Babeş-Bolyai Math. [Internet]. 2016 Mar. 30 [cited 2025 Apr. 19];61(1):87-94. Available from: https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/5520