HASSAN, T. Oscillation criterion for two-dimensional dynamic systems on time scales. Tamkang Journal of Mathematics, [S. l.], v. 44, n. 3, p. 227–232, 2012. DOI: 10.5556/j.tkjm.44.2013.1189. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/1189. Acesso em: 4 may. 2024.