TANG, X. H. Oscillation for nonlinear delay difference equations. Tamkang Journal of Mathematics, [S. l.], v. 32, n. 4, p. 275–280, 2001. DOI: 10.5556/j.tkjm.32.2001.342. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/342. Acesso em: 19 apr. 2024.