Riebel, J. (1963). How to write successful business letters. Taraporcvala & sons co.
Čikaški stil citiranjaRiebel, J.P. How to Write Successful Business Letters. Bombay: Taraporcvala & sons co, 1963.
MLA način citiranjaRiebel, J.P. How to Write Successful Business Letters. Taraporcvala & sons co, 1963.
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