VAISAKH VENU; JOMOL T JOSEPH. On Pre-Closure Sets in Topological Space. International Journal of Mathematics And its Applications, [S. l.], v. 4, n. 1 - B, p. 173–174, 2016. Disponível em: http://ijmaa.in/index.php/ijmaa/article/view/584. Acesso em: 19 may. 2024.