Soars, L., Soars, J., Hancock, P., & Storton, R. (2019). Headway: Advanced Teacher's Guide (quinta edición.). Oxford University Press.
Chicago Style (17. basım) AtıfSoars, Liz, John Soars, Paul Hancock, ve Richard Storton. Headway: Advanced Teacher's Guide. quinta edición. Oxford: Oxford University Press, 2019.
MLA (9th ed.) AtıfSoars, Liz, et al. Headway: Advanced Teacher's Guide. quinta edición. Oxford University Press, 2019.
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