Winita Mora และ Yupaporn Kemprasit. (2006) Regular elements of order-preserving transformation semigroups. Chulalongkorn University:ม.ป.ท.Winita Mora และ Yupaporn Kemprasit. 2006. Regular elements of order-preserving transformation semigroups. ม.ป.ท.:Chulalongkorn University;Winita Mora และ Yupaporn Kemprasit. Regular elements of order-preserving transformation semigroups. ม.ป.ท.:Chulalongkorn University, 2006. Print.