Wainwright, G. R. (2000). Tricky business letters: Persuasive tactics on paper. Prentice Hall.
Chicago-viite (17. p.)Wainwright, Gordon Ray. Tricky Business Letters: Persuasive Tactics on Paper. London: Prentice Hall, 2000.
MLA-viite (9. p.)Wainwright, Gordon Ray. Tricky Business Letters: Persuasive Tactics on Paper. Prentice Hall, 2000.
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