Srivastava, Panjkaj, and Rajkrishna Mondal. “A Hesitant Fuzzy Envelope Based Expert System in Human Decision Making”. Nepal Journal of Mathematical Sciences 2, no. 1 (April 30, 2021): 1–6. Accessed January 31, 2025. https://nepjol.info/index.php/njmathsci/article/view/36503.