APA (7th ed.) Citation

Willis, D., & Wright, J. (2006). Collins Cobuild Elementary English Grammar. HarperCollins Pub.

Chicago Style (17th ed.) Citation

Willis, Dave, and Jon Wright. Collins Cobuild Elementary English Grammar. HarperCollins Pub, 2006.

MLA (8th ed.) Citation

Willis, Dave, and Jon Wright. Collins Cobuild Elementary English Grammar. HarperCollins Pub, 2006.

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