Lougheed, L. (2020). Barron's IELTS (Sixth edition.). Barron's.
Chicago Style (17th ed.) ZitazioaLougheed, Lin. Barron's IELTS. Sixth edition. New York, NY: Barron's, 2020.
MLA (9th ed.) ZitazioaLougheed, Lin. Barron's IELTS. Sixth edition. Barron's, 2020.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.