GOODSTEIN, R. L. Diophantine Equations in Recursive Difference. MATHEMATICA SCANDINAVICA, [S. l.], v. 15, p. 43–48, 1964. DOI: 10.7146/math.scand.a-10725. Disponível em: https://www.mscand.dk/article/view/10725. Acesso em: 14 apr. 2025.