Jabbar Kadhim, Ihsan, and Sema Kadhim Jebur. “Study of Some Dynamical Concepts in General Topological Spaces”. Journal of Al-Qadisiyah for Computer Science and Mathematics, vol. 9, no. 1, Aug. 2017, pp. 12-22, https://jqcsm.qu.edu.iq/index.php/journalcm/article/view/9.