Ideals of BCK-algebras and BCI-algebras Based on a New Form of Fuzzy Set. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 16, n. 4, p. 2009–2024, 2023. DOI: 10.29020/nybg.ejpam.v16i4.4933. Disponível em: https://www.ejpam.com/ejpam/article/view/4933. Acesso em: 23 feb. 2026.