COBZAȘ, S. “Ravi P. Agarwal, Erdal Karapinar, Donal O’Regan and Antonio Francisco Roldán-López-De-Hierro; Fixed Point Theory in Metric Type Spaces, Cham: Springer, 2015, xvii+385 P. ISBN 978-3-319-24080-0 Hbk; 978-3-319-24082-4 Ebook)”. Studia Universitatis Babeș-Bolyai Mathematica 61, no. 3 (September 30, 2016): 389–390. Accessed February 5, 2025. https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/5606.