Cita APA (7a ed.)

Warshawsky, D. (1982). Spectrum 1: A communicative course in English. Regents Publishing Company.

Cita Chicago Style (17a ed.)

Warshawsky, Diane. Spectrum 1: A Communicative Course in English. N.York: Regents Publishing Company, 1982.

Cita MLA (9a ed.)

Warshawsky, Diane. Spectrum 1: A Communicative Course in English. Regents Publishing Company, 1982.