CHEN, C.-P.; QI, F. A double inequality for remainder of power series of tangent function. Tamkang Journal of Mathematics, [S. l.], v. 34, n. 4, p. 351–356, 2003. DOI: 10.5556/j.tkjm.34.2003.236. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/236. Acesso em: 26 apr. 2024.