Note on Intuitionistic Fuzzy (Normal) Subgroups or Vague (normal) Subgroups. Global Journal of Science Frontier Research, [S. l.], v. 15, n. F2, p. 37–52, 2015. Disponível em: https://www.journalofscience.org/index.php/GJSFR/article/view/1534. Acesso em: 14 aug. 2026.