TEAM, S. Regularity of Semihypergroups of Infinite Matrices: S. Chaopraknoi, N. Triphop. Thai Journal of Mathematics, [S. l.], v. 4, n. 3, p. 7–11, 2006. Disponível em: https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/62. Acesso em: 17 may. 2024.