Wipawee Yothipitak และ Artiwan Shotipruk. (2007) Optimization of supercritical carbon dioxide extraction of essential oil from Amomum krevanh Pierre. Chulalongkorn University:ม.ป.ท.Wipawee Yothipitak และ Artiwan Shotipruk. 2007. Optimization of supercritical carbon dioxide extraction of essential oil from Amomum krevanh Pierre. ม.ป.ท.:Chulalongkorn University;Wipawee Yothipitak และ Artiwan Shotipruk. Optimization of supercritical carbon dioxide extraction of essential oil from Amomum krevanh Pierre. ม.ป.ท.:Chulalongkorn University, 2007. Print.