Ruth Gairns. (2003). Natural english (upper-intermediate teacher's book). Oxford, NY: Oxford Univ. Press.
Čikaški stil citiranjaRuth Gairns. Natural English (upper-intermediate Teacher's Book). Oxford, NY: Oxford Univ. Press, 2003.
MLA način citiranjaRuth Gairns. Natural English (upper-intermediate Teacher's Book). Oxford, NY: Oxford Univ. Press, 2003.
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