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2. Politeness: Some Universals in Language Usage;Brown,1987
3. ‘Kotoba’ Shiriizu 1: Keego,1974
4. Bunkachō, 2006–2008. Heesee 17-, 18-, 19-nendo ‘Kokugo ni kansuru Yoron Chōsa’ no Kekka ni tsuite. www.bunka.go.jp/kokugo_nihongo/yoronchousa/h17/kekka.html, …/yoronchousa/h18/kekka.html, …/yoronchousa/h19/kekka.html (accessed 27.05.10).
5. The use of addressee honorifics in Japanese elementary school classrooms;Cook,1996