RAJAGOPAL, C. T. Theorems on the Product of Two Summability Methods with Applications. The Journal of the Indian Mathematical Society, [S. l.], v. 18, n. 1, p. 88–105, 1954. DOI: 10.18311/jims/1954/17019. Disponível em: http://informaticsjournals.com/index.php/jims/article/view/17019. Acesso em: 4 may. 2024.