FUZZY β-SETS AND FUZZY βS –SETS IN FUZZY TOPOLOGICAL SPACES. Journal of Pharmaceutical Negative Results, [S. l.], p. 1906–1910, 2023. DOI: 10.47750/pnr.2023.14.02.237. Disponível em: https://pnrjournal.com/index.php/home/article/view/7655.. Acesso em: 8 jun. 2026.