Cita APA (7th ed.)
Soars, J., & Soars, L. (1989). Headway. Oxford university press.
Cita Chicago (17th ed.)
Soars, John, i Liz Soars. Headway. London: Oxford university press, 1989.
Cita MLA (9th ed.)
Soars, John, i Liz Soars. Headway. Oxford university press, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.