Matina J. Rassias, M. Arunkumar and P. Agilan (2018) “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. India, 6(01), pp. 162–176. doi: 10.26637/MJM0601/0022.