S. Murthy, V. Govindhan, and M. Sree Shanmuga Velan. “Generalized U - H Stability of New N - Type of Additive Quartic Functional Equation in Non - Archimedean Orthogonally Space”. International Journal of Mathematics And Its Applications, vol. 5, no. 2 - A, Apr. 2017, pp. 1-11, https://ijmaa.in/index.php/ijmaa/article/view/790.