BOONPOK, C.; KHAMPAKDEE, J. (Λ, sp)-open Sets in Topological Spaces. European Journal of Pure and Applied Mathematics, [S. l.], v. 15, n. 2, p. 572–588, 2022. DOI: 10.29020/nybg.ejpam.v15i2.4276. Disponível em: https://ejpam.com/index.php/ejpam/article/view/4276. Acesso em: 5 dec. 2022.