Nattida Pattaraworathum และ Chansongklod Gajaseni. (2007) A case study of culture teaching practices of upper secondary school English teachers. Chulalongkorn University:ม.ป.ท.Nattida Pattaraworathum และ Chansongklod Gajaseni. 2007. A case study of culture teaching practices of upper secondary school English teachers. ม.ป.ท.:Chulalongkorn University;Nattida Pattaraworathum และ Chansongklod Gajaseni. A case study of culture teaching practices of upper secondary school English teachers. ม.ป.ท.:Chulalongkorn University, 2007. Print.