Tuyen, Pham Nguyen Kim, Le Hoang Duy, and Nguyen Kim Phi Phung. “Four Flavonoids from Hedyotis Nigricans”. <i>Vietnam Journal of Chemistry</i> 48, no. 5 (August 15, 2012). Accessed April 4, 2026. https://vjst.vast.vn/vjchem/article/view/2175.