Citazione Stile APA (7a Edizione)

Verderber, K. S., Sellnow, D. D., & Verderber, R. F. (2015). Speak2 (Student Edition.). Cengage Learning.

Citazione stile Chigago Style (17a edizione)

Verderber, Kathleen S., Deanna D. Sellnow, e Rudolph F. Verderber. Speak2. Student Edition. Boston, MA: Cengage Learning, 2015.

Citatione MLA (9a ed.)

Verderber, Kathleen S., et al. Speak2. Student Edition. Cengage Learning, 2015.