R. KHAN, A. KHAN, H. U. KHAN, and F. M. KHAN. “Uni-Soft Filters of Ordered Semigroups”. Sindh University Research Journal - SURJ (Science Series) 48, no. 4 (December 20, 2016). Accessed July 30, 2026. https://sujo.usindh.edu.pk/index.php/SURJ/article/view/4796.