ESSÉN, M.; LEWIS, J. L. The Generalized Ahlfors-Heins Theorem in Certain $d$-Dimensional Cones. MATHEMATICA SCANDINAVICA, [S. l.], v. 33, p. 113–129, 1973. DOI: 10.7146/math.scand.a-11477. Disponível em: https://www.mscand.dk/article/view/11477. Acesso em: 29 apr. 2024.