APA (7th ed.) Citation

Travis, P., & Harrison, L. (2013). Practice tests for IELTS. HarperCollins Publishers.

Chicago Style (17th ed.) Citation

Travis, Peter, and L. Harrison. Practice Tests for IELTS. London: HarperCollins Publishers, 2013.

MLA (9th ed.) Citation

Travis, Peter, and L. Harrison. Practice Tests for IELTS. HarperCollins Publishers, 2013.

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