Watchara Teparos และ Yupaporn Kemprasit. (2006) Multi-valued homomorphisms of semigroups and regularity of semigroups of multi-valued functions. Chulalongkorn University:ม.ป.ท.Watchara Teparos และ Yupaporn Kemprasit. 2006. Multi-valued homomorphisms of semigroups and regularity of semigroups of multi-valued functions. ม.ป.ท.:Chulalongkorn University;Watchara Teparos และ Yupaporn Kemprasit. Multi-valued homomorphisms of semigroups and regularity of semigroups of multi-valued functions. ม.ป.ท.:Chulalongkorn University, 2006. Print.