Lougheed, L. (2007). Barron's IELTS: International English language testing system. Tp.HCM: Nxb. Trẻ.
Chicago Style aipamenaLougheed, Lin. Barron's IELTS: International English Language Testing System. Tp.HCM: Nxb. Trẻ, 2007.
MLA aipamenaLougheed, Lin. Barron's IELTS: International English Language Testing System. Tp.HCM: Nxb. Trẻ, 2007.
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