Cita APA (7a ed.)

(2019). TOEFL® iBT prep plus 2020-2021. Kaplan Publishing.

Cita Chicago Style (17a ed.)

TOEFL® IBT Prep Plus 2020-2021. New York: Kaplan Publishing, 2019.

Cita MLA (9a ed.)

TOEFL® IBT Prep Plus 2020-2021. Kaplan Publishing, 2019.