Ur P. Penny. (2006). Grammar Practice Activities. A practical guide for teachers. Cambridge, Cambridge University Press, 2006.
Chicago-viite (17. p.)Ur P. Penny. Grammar Practice Activities. A Practical Guide for Teachers. Cambridge, Cambridge University Press, 2006, 2006.
MLA-viite (9. p.)Ur P. Penny. Grammar Practice Activities. A Practical Guide for Teachers. Cambridge, Cambridge University Press, 2006, 2006.
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