Keerati Suppatkul และ Chansongklod Gajaseni. (2009) Effects of teachers' English accents on listening comprehension ability of upper secondary school students. Chulalongkorn University:ม.ป.ท.Keerati Suppatkul และ Chansongklod Gajaseni. 2009. Effects of teachers' English accents on listening comprehension ability of upper secondary school students. ม.ป.ท.:Chulalongkorn University;Keerati Suppatkul และ Chansongklod Gajaseni. Effects of teachers' English accents on listening comprehension ability of upper secondary school students. ม.ป.ท.:Chulalongkorn University, 2009. Print.