Soars, L., & Liz & John Soars with Jop Devoy. (1998). New Headway English Course: Upper-intermediate (Workbook with key). Oxford: Oxford University Press.
Chicago Style aipamenaSoars, Liz, và Liz & John Soars with Jop Devoy. New Headway English Course: Upper-intermediate (Workbook With Key). Oxford: Oxford University Press, 1998.
MLA aipamenaSoars, Liz, và Liz & John Soars with Jop Devoy. New Headway English Course: Upper-intermediate (Workbook With Key). Oxford: Oxford University Press, 1998.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.