Guffey, M. E., & Loewy, D. (2010). Essentials of business communication (8th ed.). South-Western/Cengage Learning.
Chicago Style (17. basım) AtıfGuffey, Mary Ellen, ve Dana Loewy. Essentials of Business Communication. 8th ed. Mason, Ohio: South-Western/Cengage Learning, 2010.
MLA (9th ed.) AtıfGuffey, Mary Ellen, ve Dana Loewy. Essentials of Business Communication. 8th ed. South-Western/Cengage Learning, 2010.
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