USHIJIMA, A. Dirichlet polyhedra for simplex groups of spherical, Euclidean or hyperbolic spaces. Annales Fennici Mathematici, [S. l.], v. 46, n. 1, p. 123–127, 2021. Disponível em: https://afm.journal.fi/article/view/109398. Acesso em: 7 apr. 2025.