APA (7th ed.) Citation

DEBSKA. (1991). Upgrading your English. Univ.Press..

Chicago Style (17th ed.) Citation

DEBSKA. Upgrading Your English. Oxford: Univ.Press., 1991.

MLA (9th ed.) Citation

DEBSKA. Upgrading Your English. Univ.Press., 1991.

Warning: These citations may not always be 100% accurate.