Noiri, Takashi, and Valeriu Popa. “A Note on Modifications of \(rg\)-Closed Sets in Topological Spaces”. CUBO, A Mathematical Journal 15, no. 2 (June 1, 2013): 65–69. Accessed October 13, 2025. https://cubo.ufro.cl/index.php/cubo/article/view/1310.