Tipmontree และ Sarinya. (2007) The Use and the Problems of English and Intercultural Communication Skills of Thai Tourist Police Officers. University of the Thai Chamber of Commerce:ม.ป.ท.Tipmontree และ Sarinya. 2007. The Use and the Problems of English and Intercultural Communication Skills of Thai Tourist Police Officers. ม.ป.ท.:University of the Thai Chamber of Commerce;Tipmontree และ Sarinya. The Use and the Problems of English and Intercultural Communication Skills of Thai Tourist Police Officers. ม.ป.ท.:University of the Thai Chamber of Commerce, 2007. Print.