APA (7th ed.) Citation

Gardner, D., Knill, R., & Smith, J. (2005). Horizons: Geography 11 - 14. Nelson Thornes.

Chicago Style (17th ed.) Citation

Gardner, David, Roger Knill, and John Smith. Horizons: Geography 11 - 14. Cheltenham: Nelson Thornes, 2005.

MLA (9th ed.) Citation

Gardner, David, et al. Horizons: Geography 11 - 14. Nelson Thornes, 2005.