LJUNGGREN, Wilhelm. On an improvement of a theorem of T. Nagell concerning the Diophantine equation $Ax^3 + By^3 = C$. Mathematica Scandinavica, Berkeley, CA, United States, v. 1, p. 297–309, 1953. DOI: 10.7146/math.scand.a-10388. Disponível em: https://journals.msp.org/mscand/article/view/2935. Acesso em: 8 sep. 2026.