HARARY, F.; KAINEN, P. C.; SCHWENK, A. J. A Maximal Toroidal Graph which is not a Triangulation. Mathematica Scandinavica, Berkeley, CA, United States, v. 33, p. 108–112, 1973. DOI: 10.7146/math.scand.a-11476. Disponível em: https://journals.msp.org/mscand/article/view/2189. Acesso em: 25 jul. 2026.