[1]
John M. Rassias, M. Arunkumar, E. Sathya, and N. Mahesh Kumar, “Generalized Ulam - Hyers stability of on (AQQ): Additive-quadratic-Quartic functional equation”,
Malaya J. Mat.
, vol. 5, no. 01, pp. 122–142, Jan. 2017.