Lougheed, L. (2010). Barron’s IELTS: International Language Testing System (2nd ed.). Tp.HCM: Trẻ.
Chicago Style aipamenaLougheed, Lin. Barron’s IELTS: International Language Testing System. 2nd ed. Tp.HCM: Trẻ, 2010.
MLA aipamenaLougheed, Lin. Barron’s IELTS: International Language Testing System. 2nd ed. Tp.HCM: Trẻ, 2010.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.