TVERBERG, H. On Brooks’ theorem and some related results. MATHEMATICA SCANDINAVICA, [S. l.], v. 52, p. 37–40, 1983. DOI: 10.7146/math.scand.a-11991. Disponível em: https://www.mscand.dk/article/view/11991. Acesso em: 4 may. 2024.