Ur, P. (1988). Grammar practice activities: Practical guide for teachers. Cambridge: Cambridge University Press.
Chicago Style aipamenaUr, Penny. Grammar Practice Activities: Practical Guide for Teachers. Cambridge: Cambridge University Press, 1988.
MLA aipamenaUr, Penny. Grammar Practice Activities: Practical Guide for Teachers. Cambridge: Cambridge University Press, 1988.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.