GOWER, R. (1993). Speaking upper - intermediate. Oxford University Press.
Lua i Stíl Chicago (17ú heag.)GOWER, Roger. Speaking Upper - Intermediate. Oxford: Oxford University Press, 1993.
Lua MLA (9ú heag.)GOWER, Roger. Speaking Upper - Intermediate. Oxford University Press, 1993.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.