Soars, J., & Soars, L. (1993). Headway intermediate student's book & pre-intermediate workbook. Oxford: Oxford University Press.
Παραπομπή Chicago StyleSoars, John, και Liz Soars. Headway Intermediate Student's Book & Pre-intermediate Workbook. Oxford: Oxford University Press, 1993.
Παραπομπή MLASoars, John, και Liz Soars. Headway Intermediate Student's Book & Pre-intermediate Workbook. Oxford: Oxford University Press, 1993.
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