Comparing letters of complaint in Philippine english and Singaporean english reactions using a semantic differential scale Ma. Lourdes S. Bautista dan Marilu B. ranosa-Madrunio
Artikel Jurnal
Standardising English : essay in the history of language change / edited by Joseph B. Trahern
The University of Tenessee Press, 1989
Buku Teks
King, F.W
English business letters : commercial correspondence for foreign students/F.W. King, D. Ann Cree.
Longmans , 1979
Buku Teks
Seglin, Jeffrey L.
The AMA handbook of business letters
[American Management Association, American Management Association], 2002
eBooks
Seglin, Jeffrey L.
The AMA handbook of business letters
Amacom, 1996
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