GOODSTEIN, R. L. On non-constructive theorems of analysis and the decision problem. MATHEMATICA SCANDINAVICA, [S. l.], v. 3, p. 261–263, 1955. DOI: 10.7146/math.scand.a-10444. Disponível em: https://www.mscand.dk/article/view/10444. Acesso em: 29 apr. 2024.