Kreungngern, Danchai, Anek Hale, and Boonyakrit Rattanapun. 2017. “Determination ursolic acid and antioxidantin Grass jelly (Mesona procumbens Hemsley.)”. Food and Applied Bioscience Journal 1 (2):90-101. https://li01.tci-thaijo.org/index.php/fabjournal/article/view/77369.