Costinett, S. (1985). Spectrum 5: A communicative course in english. Prentice Hall Regents.
Cita Chicago Style (17a ed.)Costinett, Sandra. Spectrum 5: A Communicative Course in English. London: Prentice Hall Regents, 1985.
Cita MLA (9a ed.)Costinett, Sandra. Spectrum 5: A Communicative Course in English. Prentice Hall Regents, 1985.
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