Cita APA (7th ed.)

Keller, D. P., & Thrush, E. A. (1987). Interactions I. A speaking activities book (1a. ed.). Random House.

Cita Chicago (17th ed.)

Keller, Deborah Poole, i Emity Austin Thrush. Interactions I. A Speaking Activities Book. 1a. ed. Nueva York: Random House, 1987.

Cita MLA (9th ed.)

Keller, Deborah Poole, i Emity Austin Thrush. Interactions I. A Speaking Activities Book. 1a. ed. Random House, 1987.