TANG, Jian; XIN, Xiaolong; XIE, Xiangyun. CHARACTERIZATIONS OF ORDERED SEMIHYPERGROUPS BASED ON ORDERED FUZZY POINTS. Italian Journal of Pure and Applied Mathematics, [S. l.], v. 39, p. 290–311, 2018. Disponível em: https://journals.uniurb.it/index.php/ijpam/article/view/6929. Acesso em: 7 oct. 2026.