Vipavee Pichetpongsa และ Paveena Chaovalitwongse. (2006) Development of production planning system for snack industry. Chulalongkorn University:ม.ป.ท.Vipavee Pichetpongsa และ Paveena Chaovalitwongse. 2006. Development of production planning system for snack industry. ม.ป.ท.:Chulalongkorn University;Vipavee Pichetpongsa และ Paveena Chaovalitwongse. Development of production planning system for snack industry. ม.ป.ท.:Chulalongkorn University, 2006. Print.