Citazione Stile APA (7a Edizione)

Costinett, S., & Byrd, D. R. H. (1993). Spectrum 2: A communicative course in English. Student book, 2A (1a. ed.). Regents.

Citazione stile Chigago Style (17a edizione)

Costinett, Sandra, e Donald R. H. Byrd. Spectrum 2: A Communicative Course in English. Student Book, 2A. 1a. ed. Englewood Cliffs: Regents, 1993.

Citatione MLA (9a ed.)

Costinett, Sandra, e Donald R. H. Byrd. Spectrum 2: A Communicative Course in English. Student Book, 2A. 1a. ed. Regents, 1993.