Verderber, K. S., Sellnow, D. D., & Verderber, R. F. (2015). Speak2 (Student Edition.). Cengage Learning.
Chicago Style (17. basım) AtıfVerderber, Kathleen S., Deanna D. Sellnow, ve Rudolph F. Verderber. Speak2. Student Edition. Boston, MA: Cengage Learning, 2015.
MLA (9th ed.) AtıfVerderber, Kathleen S., et al. Speak2. Student Edition. Cengage Learning, 2015.
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