APA (7th ed.) Citation

Crystal, D., & Barton, G. (2009). Discover grammar (15. impr.). Longman.

Chicago Style (17th ed.) Citation

Crystal, David, and Geoff Barton. Discover Grammar. 15. impr. Harlow: Longman, 2009.

MLA (9th ed.) Citation

Crystal, David, and Geoff Barton. Discover Grammar. 15. impr. Longman, 2009.

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