Gower, R. (2005). Grammar in practice 5 (First edition.). Cambridge University Press.
Chicago Style (17th ed.) ZitazioaGower, Roger. Grammar in Practice 5. First edition. Cambridge: Cambridge University Press, 2005.
MLA (9th ed.) ZitazioaGower, Roger. Grammar in Practice 5. First edition. Cambridge University Press, 2005.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.