Sharpe, P. J. (1999). How to prepare for the TOEFL test: Test of English as a foreign language (10th ed.). Barron's Educational.
Chicago-viite (17. p.)Sharpe, Pamela J. How to Prepare for the TOEFL Test: Test of English as a Foreign Language. 10th ed. Hauppauge, NY: Barron's Educational, 1999.
MLA-viite (8. p.)Sharpe, Pamela J. How to Prepare for the TOEFL Test: Test of English as a Foreign Language. 10th ed. Barron's Educational, 1999.
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