Witthawas Phanthawimol และ Yupaporn Kemprasit. (2010) Homomorphisms of some hypergroups. Chulalongkorn University:ม.ป.ท.Witthawas Phanthawimol และ Yupaporn Kemprasit. 2010. Homomorphisms of some hypergroups. ม.ป.ท.:Chulalongkorn University;Witthawas Phanthawimol และ Yupaporn Kemprasit. Homomorphisms of some hypergroups. ม.ป.ท.:Chulalongkorn University, 2010. Print.