Gartside, L. (Leonard)
Model business letters : a classified selection of modern business letters for use in school and in business
Macdonald and Evans, 1982
 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
 Buku Referensi
Seglin, Jeffrey L.
The AMA handbook of business letters
[American Management Association;;;, ], 2012
 eBooks
Modern business
Alexander Hamilton Institute
Alexander Hamilton Institute, 1971
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