Cita APA (7a ed.)

Warshawsky, D. (1983). Spectrum 3: A communicative course in english. Prentice Hall Regents.

Cita Chicago Style (17a ed.)

Warshawsky, Diane. Spectrum 3: A Communicative Course in English. London: Prentice Hall Regents, 1983.

Cita MLA (9a ed.)

Warshawsky, Diane. Spectrum 3: A Communicative Course in English. Prentice Hall Regents, 1983.