VUORINEN, Matti. On the Iversen-Tsuji theorem quasiregular mappings. Mathematica Scandinavica, Berkeley, CA, United States, v. 41, p. 90–98, 1977. DOI: 10.7146/math.scand.a-11704. Disponível em: https://journals.msp.org/mscand/article/view/1946. Acesso em: 25 jul. 2026.