CHENG, S.-S.; LI, H.-J. BOUNDED SOLUTIONS OF NONLINEAR DIFFERENCE EQUATIONS. Tamkang Journal of Mathematics, [S. l.], v. 21, n. 2, p. 137–142, 1990. DOI: 10.5556/j.tkjm.21.1990.4648. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4648. Acesso em: 3 may. 2024.