Yodpornpin Wiratkasem. 2002. The written language of opinion : an examination of "Postbag". Field of Study Communicative English, Ramkhamhaeng University;
Yodpornpin Wiratkasem. (2002) The written language of opinion : an examination of "Postbag" . Ramkhamhaeng University/Bangkok.
Yodpornpin Wiratkasem. The written language of opinion : an examination of "Postbag". . Bangkok:Ramkhamhaeng University, 2002.
Yodpornpin Wiratkasem. (2002) The written language of opinion : an examination of "Postbag" . Ramkhamhaeng University/Bangkok.