R. Thangappan. On $\beta^*$-open and $\beta^*$-closed sets in fuzzy topological space. Malaya J. Mat. [Internet]. 2021 Jan. 1 [cited 2024 Jul. 16];9(01):291-4. Available from: https://www.malayajournal.org/index.php/mjm/article/view/1019