APA-viite (7. p.)
Ur, P. (1988). Grammar practice activities: A practical guide for teachers. CUP.
Chicago-viite (17. p.)
Ur, Penny. Grammar Practice Activities: A Practical Guide for Teachers. Cambridge: CUP, 1988.
MLA-viite (9. p.)
Ur, Penny. Grammar Practice Activities: A Practical Guide for Teachers. CUP, 1988.
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