Team, Support. 2010. “A Fixed Point Approach to the Generalized Hyers-Ulam Stability of Reciprocal Difference and Adjoint Functional Equations: K. Ravi, J.M. Rassias, B.V. Senthil Kumar”. Thai Journal of Mathematics 8 (3):469-81. https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/215.