BEHROUZI, F. The Stone–Čech Compactification of Groupoids. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 67, n. 4, p. 456–466, 2015. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1996. Acesso em: 27 apr. 2025.