СУПРУН, О. М. Half-group of non-compact discrete subgroups relatively to operation of topological generation of subgroups. Proceedings of National Aviation University, [S. l.], v. 2, n. 1, p. 238–242, 1999. DOI: 10.18372/2306-1472.2.8997. Disponível em: https://jrnl.nau.edu.ua/index.php/visnik/article/view/8997. Acesso em: 18 may. 2024.