DRAGOMIR, S. S.; KHAN, L. Two discrete inequalities of Gr"uss type via P’olya-Szeg"o and Shisha-Mond results for real numbers. Tamkang Journal of Mathematics, [S. l.], v. 35, n. 2, p. 117-128, 2004. DOI: 10.5556/j.tkjm.35.2004.213. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/213. Acesso em: 19 sep. 2021.