Sharpe, P. J. (2006). Barron's how to prepare for the Toefl iBT: Test of English as a foreign language: Internet - Based test. Thành phố Hồ Chí Minh: Trẻ.
Παραπομπή Chicago StyleSharpe, Pamela J. Barron's How to Prepare for the Toefl IBT: Test of English As a Foreign Language: Internet - Based Test. Thành phố Hồ Chí Minh: Trẻ, 2006.
Παραπομπή MLASharpe, Pamela J. Barron's How to Prepare for the Toefl IBT: Test of English As a Foreign Language: Internet - Based Test. Thành phố Hồ Chí Minh: Trẻ, 2006.
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