HALLBERG, F. Infinite Series and Arithmetical Functions. The Journal of the Indian Mathematical Society, [S. l.], v. 9, n. 5, p. 174–186, 1917. DOI: 10.18311/jims/1917/17616. Disponível em: https://www.informaticsjournals.com/index.php/jims/article/view/17616. Acesso em: 29 apr. 2024.