DANIEL SCHWAB, Emil. The bicyclic semigroup as the quotient inverse semigroup by any gauge inverse submonoid. Journal of Algebra Combinatorics Discrete Structures and Applications, [S. l.], v. 9, n. 2, p. 123–131, 2022. DOI: 10.13069/jacodesmath.1112177. Disponível em: https://jacodesmath.com/index.php/jacodesmath/article/view/226. Acesso em: 12 sep. 2026.