Gaya APA

Toefl Preparation. (2011). Yogyakarta.: BLTI.

Gaya Chicago

Toefl Preparation. . Yogyakarta.: BLTI, 2011. Text.

Gaya MLA

Toefl Preparation. . Yogyakarta.: BLTI, 2011. Text.

Gaya Turabian

Toefl Preparation. Yogyakarta.: BLTI, 2011. Print.