K. Prasad, S. Venu Madhava Sarma, D.V. Ramalinga Reddy, Y. Prabhakara Rao, P. Rangaswamy. “A Note on Anti-Fuzzy Ideals in Subtraction Semi Groups”. International Journal of Advanced Science and Technology, Vol. 29, no. 06, June 2020, pp. 8557-62, http://sersc.org/journals/index.php/IJAST/article/view/25304.