Cita APA (7th ed.)

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

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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