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