Goodworth, C. (1986). The secrets of successful business letters. Heinemann.
Čikaški stil citiranja (17. izdanje)Goodworth, Clive. The Secrets of Successful Business Letters. Oxford: Heinemann, 1986.
MLA način citiranja (9. izdanje)Goodworth, Clive. The Secrets of Successful Business Letters. Heinemann, 1986.
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