Hewings, M. (2007). Advanced english grammar. Cambridge University Press.
Lua i Stíl Chicago (17ú heag.)Hewings, Martin. Advanced English Grammar. New Delhi: Cambridge University Press, 2007.
Lua MLA (9ú heag.)Hewings, Martin. Advanced English Grammar. Cambridge University Press, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.