K.ARJUNAN, b.Deeba, s. N. . A Research on Bipolar Valued Vague Normal Subrings of A Ring. Mathematical Statistician and Engineering Applications, [S. l.], v. 72, n. 1, p. 1926–1933, 2023. DOI: 10.17762/msea.v72i1.2611. Disponível em: https://www.philstat.org/index.php/MSEA/article/view/2611. Acesso em: 18 may. 2024.