Watsamon Saetae และ Surachai Pornpakakul. (2008) Preparation of polyglycerol-based polyurethane for slow - released fertilizer. Chulalongkorn University:ม.ป.ท.Watsamon Saetae และ Surachai Pornpakakul. 2008. Preparation of polyglycerol-based polyurethane for slow - released fertilizer. ม.ป.ท.:Chulalongkorn University;Watsamon Saetae และ Surachai Pornpakakul. Preparation of polyglycerol-based polyurethane for slow - released fertilizer. ม.ป.ท.:Chulalongkorn University, 2008. Print.