Littlejohn, A., & Hicks, D. (1998). Cambridge english for schools: Teacher's book four. Cambridge University Press.
Chicago-viite (17. p.)Littlejohn, Andrew, ja Diana Hicks. Cambridge English for Schools: Teacher's Book Four. Cambridge: Cambridge University Press, 1998.
MLA-viite (9. p.)Littlejohn, Andrew, ja Diana Hicks. Cambridge English for Schools: Teacher's Book Four. Cambridge University Press, 1998.
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