Matina J. Rassias, M. Arunkumar, and P. Agilan. “General Solution and Generalized Ulam - Hyers Stability of $r_i$-Type $n$ Dimensional Quadratic-Cubic Functional Equation in Random Normed Spaces: Direct and Fixed Point Methods”. Malaya Journal of Matematik 6, no. 01 (January 1, 2018): 162–176. Accessed November 21, 2024. https://www.malayajournal.org/index.php/mjm/article/view/794.