TEAM, S. Regular Elements of the Variant Semigroups of Transformations Preserving Double Direction Equivalences: Winita Yonthanthum. Thai Journal of Mathematics, [S. l.], v. 16, n. 1, p. 165–171, 2018. Disponível em: https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/784. Acesso em: 28 apr. 2024.