Educational Testing Service. (2021). Official guide to the toefl ibt test, sixth edition (Sixth edition.). McGraw Hill.
Lua i Stíl Chicago (17ú heag.)Educational Testing Service. Official Guide to the Toefl Ibt Test, Sixth Edition. Sixth edition. New York: McGraw Hill, 2021.
Lua MLA (9ú heag.)Educational Testing Service. Official Guide to the Toefl Ibt Test, Sixth Edition. Sixth edition. McGraw Hill, 2021.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.