SELMER, E. S. On regular Frobenius bases. MATHEMATICA SCANDINAVICA, [S. l.], v. 63, p. 109–116, 1988. DOI: 10.7146/math.scand.a-12227. Disponível em: https://www.mscand.dk/article/view/12227. Acesso em: 5 may. 2024.