HWANG, TIAN-SHOW, and GOU-SHENG YANG. “ON INTEGRAL INEQUALITIES RELATED TO OPIAL’S INEQUALITY”. Tamkang Journal of Mathematics 21, no. 2 (June 1, 1990): 177–183. Accessed July 19, 2024. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4654.