APA (7th ed.) Citation

Soars, L., & Soars, J. (1997). New headway english course: Intermediate student's book: part A, units 1-6. Oxford University Press.

Chicago Style (17th ed.) Citation

Soars, Liz, and John Soars. New Headway English Course: Intermediate Student's Book: Part A, Units 1-6. Oxford, Inglaterra: Oxford University Press, 1997.

MLA (9th ed.) Citation

Soars, Liz, and John Soars. New Headway English Course: Intermediate Student's Book: Part A, Units 1-6. Oxford University Press, 1997.