SNAITH, Victor P. A note on symmetric maps for spheres. Mathematica Scandinavica, Berkeley, CA, United States, v. 38, p. 78–80, 1976. DOI: 10.7146/math.scand.a-11617. Disponível em: https://journals.msp.org/mscand/article/view/2030. Acesso em: 25 jul. 2026.