Sawai Pongkao, and Amnuay Yothasir. “Effect of Juvenile Leaf Removal on Symbiotic N Fixation and Yield of Mungbean (Vigna radiata (L.) Wilczek)”. Agriculture and Natural Resources, vol. 29, no. 2, June 1995, pp. 246-51, https://li01.tci-thaijo.org/index.php/anres/article/view/241320.