Dragomir SS. Inequalities for orthornormal families of vectors in inner product spaces related to Buzano’s, Richard’s and Kurepa’s results. Tamkang J. Math. [Internet]. 2006 Sep. 30 [cited 2024 Apr. 24];37(3):227-35. Available from: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/168