Citazione Stile APA (7a Edizione)

Educational Testing Service. (2007). The official guide to the new toefl ibt. McGraw-Hill.

Citazione stile Chigago Style (17a edizione)

Educational Testing Service. The Official Guide to the New Toefl Ibt. New York: McGraw-Hill, 2007.

Citatione MLA (9a ed.)

Educational Testing Service. The Official Guide to the New Toefl Ibt. McGraw-Hill, 2007.