BEARDON, Alan F.; JORGENSEN, Troels. Fundamental domains for finitely generated Kleinian groups. MATHEMATICA SCANDINAVICA, [S. l.], v. 36, p. 21–26, 1975. DOI: 10.7146/math.scand.a-11559. Disponível em: https://www.mscand.dk/article/view/11559. Acesso em: 5 dec. 2025.