Guffey, M. E. (2010). Essentials of business communication 2nd ed. Cengage Learning.
Chicago Style (17. basım) AtıfGuffey, Mary Ellen. Essentials of Business Communication 2nd Ed. Cengage Learning, 2010.
MLA (8th ed.) AtıfGuffey, Mary Ellen. Essentials of Business Communication 2nd Ed. Cengage Learning, 2010.
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