Citazione Stile APA (7a Edizione)
Soars, J., & Soars, L. (1989). Headway. Student's Book: Advanced (9.impression.). Oxford University Press.
Citazione stile Chigago Style (17a edizione)
Soars, John, e Liz Soars. Headway. Student's Book: Advanced. 9.impression. Oxford: Oxford University Press, 1989.
Citatione MLA (9a ed.)
Soars, John, e Liz Soars. Headway. Student's Book: Advanced. 9.impression. Oxford University Press, 1989.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.