Guffey, M. E. (2010). Essentials of business communication 2nd ed. Cengage Learning.
Čikaški stil citiranja (17. izdanje)Guffey, Mary Ellen. Essentials of Business Communication 2nd Ed. Cengage Learning, 2010.
MLA način citiranja (8. izdanje)Guffey, Mary Ellen. Essentials of Business Communication 2nd Ed. Cengage Learning, 2010.
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