CHENG, S. S. .; MEDINA, R. . Bounded and positive solutions of discrete steady state equations. Tamkang Journal of Mathematics, [S. l.], v. 31, n. 2, p. 131–136, 2000. DOI: 10.5556/j.tkjm.31.2000.404. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/404. Acesso em: 19 aug. 2022.