Shape, P. J. (2003). How to prepare for the TOEFL test: Test of English as a foreign language. TR.
Chicago-tyylinen lähdeviittausShape, Palmela J. How to Prepare for the TOEFL Test: Test of English As a Foreign Language. TR, 2003.
MLA-viiteShape, Palmela J. How to Prepare for the TOEFL Test: Test of English As a Foreign Language. TR, 2003.
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