Pham, T. T. T., & Lê, T. T. (2011). A study of pre-sequences in English and Vietnamese apology. Đà Nẵng: The University of Da Nang.
Chicago-tyylinen lähdeviittausPham, Thi Thu Thao., ja Tấn Thi Lê. A Study of Pre-sequences in English and Vietnamese Apology. Đà Nẵng: The University of Da Nang, 2011.
MLA-viitePham, Thi Thu Thao., ja Tấn Thi Lê. A Study of Pre-sequences in English and Vietnamese Apology. Đà Nẵng: The University of Da Nang, 2011.
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