M. Hasan, Haji. “A New Type of ξ-Open Sets Based on Operations”. AL-Rafidain Journal of Computer Sciences and Mathematics 9, no. 1 (June 25, 2025): 181–189. Accessed August 5, 2025. https://rjps.uomosul.edu.iq/index.php/csmj/article/view/19698.