MOSSIGE, Svein. On extremal $h$-bases $A_4$. Mathematica Scandinavica, Berkeley, CA, United States, v. 61, p. 5–16, 1987. DOI: 10.7146/math.scand.a-12188. Disponível em: https://journals.msp.org/mscand/article/view/1476. Acesso em: 25 jul. 2026.