M, A., C. H.M, M. A.M, and M. M.R. “A Comparitive Study on Antioxidant Activity of Flavonoids: Structure-Activity Relationships”. Malaysian Journal of Science, vol. 24, no. 1, Jan. 2005, pp. 187-90, https://malindojournal.um.edu.my/index.php/MJS/article/view/8970.