Cita APA (7a ed.)

Sheldon, C., & Yoxon, M. (2007). Environmental management systems: A step-by-step guide to implementation and maintenance (3rd ed.). Earthscan.

Cita Chicago Style (17a ed.)

Sheldon, Christopher, y Mark Yoxon. Environmental Management Systems: A Step-by-step Guide to Implementation and Maintenance. 3rd ed. London ; Sterling, VA: Earthscan, 2007.

Cita MLA (8a ed.)

Sheldon, Christopher, y Mark Yoxon. Environmental Management Systems: A Step-by-step Guide to Implementation and Maintenance. 3rd ed. Earthscan, 2007.