NIMBHORKAR, S. K.; WASADIKAR, M. P. N-Normal Join-Semilattices. The Journal of the Indian Mathematical Society, [S. l.], v. 72, n. 1-4, p. 53–57, 2005. Disponível em: http://informaticsjournals.com/index.php/jims/article/view/21815. Acesso em: 4 may. 2024.