LIMA, Asvald. An application of a theorem of Hirsberg and Lazar. Mathematica Scandinavica, Berkeley, CA, United States, v. 38, p. 325–340, 1976. DOI: 10.7146/math.scand.a-11639. Disponível em: https://journals.msp.org/mscand/article/view/2006. Acesso em: 25 jul. 2026.