GROSS, Kenneth B. A product theorem for Skolem sequences. Mathematica Scandinavica, Berkeley, CA, United States, v. 38, p. 262–264, 1976. DOI: 10.7146/math.scand.a-11633. Disponível em: https://journals.msp.org/mscand/article/view/2010. Acesso em: 25 jul. 2026.