EILENBERG, S. Abstract Description of some Basic Functors. The Journal of the Indian Mathematical Society, [S. l.], v. 24, n. 1-2, p. 231–234, 1960. DOI: 10.18311/jims/1960/16908. Disponível em: https://www.informaticsjournals.com/index.php/jims/article/view/16908. Acesso em: 4 may. 2024.