CALDERON, C.; DE VELASCO, M. J. Sums of Power Free Integers on Progressions. The Journal of the Indian Mathematical Society, [S. l.], v. 66, n. 1-4, p. 33–41, 1999. Disponível em: http://www.informaticsjournals.com/index.php/jims/article/view/21926. Acesso em: 5 may. 2024.