GUDMUNDSSON, S.; WOOD, J. C. Multivalued harmonic morphisms. MATHEMATICA SCANDINAVICA, [S. l.], v. 73, p. 127–155, 1993. DOI: 10.7146/math.scand.a-12460. Disponível em: https://www.mscand.dk/article/view/12460. Acesso em: 1 may. 2024.