Gaya APA

Essential grammar use : a selfstudy reference and practice book for elementary students of english with answers. (1990). New York: Press Syndicate of the University of Cambridge The Pitt Building.

Gaya MLA

Essential grammar use : a selfstudy reference and practice book for elementary students of english with answers. . New York: Press Syndicate of the University of Cambridge The Pitt Building, 1990. Text.