Fuzzy Duplex UP-Algebras. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 13, n. 3, p. 459–471, 2020. DOI: 10.29020/nybg.ejpam.v13i3.3752. Disponível em: https://www.ejpam.com/ejpam/article/view/3752. Acesso em: 23 feb. 2026.