John M. Rassias, M. Arunkumar, and P. Agilan. 2015. “Solution and Ulam - Hyers Stability of an Additive - Quadratic Functional Equation in Banach Space: Hyers Direct and Fixed Point Methods”. International Journal of Mathematics And Its Applications 3 (4 - D):17-46. http://ijmaa.in/index.php/ijmaa/article/view/512.