Arunkumar, M., and S. Karthikeyan. “Solution and Intuitionistic Fuzzy Stability of N- Dimensional Quadratic Functional Equation: Direct and Fixed Point Methods”. International Journal of Advanced Mathematical Sciences, vol. 2, no. 1, Jan. 2014, pp. 21-33, https://doi.org/10.14419/ijams.v2i1.1498.