Govindan, Vediyappan, Choonkil Park, Sandra Pinelas, and Themistocles M. Rassias. “Hyers-Ulam Stability of an Additive-Quadratic Functional Equation”. CUBO, A Mathematical Journal 22, no. 2 (August 22, 2020): 233–255. Accessed May 9, 2024. https://www.perspectivasdelacomunicacion.cl/ojs/index.php/cubo/article/view/2365.