ASAAD, B. A. Operation Approaches on Ps-Open Sets and its Separation Axioms. Science Journal of University of Zakho, [S. l.], v. 4, n. 2, p. 236–243, 2016. Disponível em: https://sjuoz.uoz.edu.krd/index.php/sjuoz/article/view/355. Acesso em: 20 apr. 2024.