APA (7th ed.) Citation
O'Driscoll, J. (1990). Penguin Basic English Grammar: Exercises (1. ed.). Penguin Books.
Chicago Style (17th ed.) Citation
O'Driscoll, James. Penguin Basic English Grammar: Exercises. 1. ed. London: Penguin Books, 1990.
MLA (9th ed.) Citation
O'Driscoll, James. Penguin Basic English Grammar: Exercises. 1. ed. Penguin Books, 1990.
Warning: These citations may not always be 100% accurate.