Sharpe, P. J. (1999). Barron's how to prepare for the TOEFL: Test of English as a foreign language (9th ed.). New York: BARRON'S.
Παραπομπή Chicago StyleSharpe, Pamela J. Barron's How to Prepare for the TOEFL: Test of English As a Foreign Language. 9th ed. New York: BARRON'S, 1999.
Παραπομπή MLASharpe, Pamela J. Barron's How to Prepare for the TOEFL: Test of English As a Foreign Language. 9th ed. New York: BARRON'S, 1999.
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