AkkouchiM., BounabatA., & RhaliM. L. (2011). Fixed point approach to the stability of an integral equation in the sense of Ulam-Hyers-Rassias. Annales Mathematicae Silesianae, 25, 27-44. Retrieved from https://journals.us.edu.pl/index.php/AMSIL/article/view/14019