Lougheed, L. (2021). Barron's IELTS (Fourth edition.). Kaplan, Inc., d/b/a Barron's Educational Series.
Chicago-viite (17. p.)Lougheed, Lin. Barron's IELTS. Fourth edition. New York, NY: Kaplan, Inc., d/b/a Barron's Educational Series, 2021.
MLA-viite (9. p.)Lougheed, Lin. Barron's IELTS. Fourth edition. Kaplan, Inc., d/b/a Barron's Educational Series, 2021.
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