Boonrue Wilaipon, Nuanchan Wilaipon, & Rut Akkasaeng. (1989). Study on Yields of Grasses and Legumes under Fertile Soil at Khon Kaen. Agriculture and Natural Resources, 23(4), 340–348. retrieved from https://li01.tci-thaijo.org/index.php/anres/article/view/242315