APA-viite

Christopher Sheldon. (2007). Environmental management systems: Step by step guide to implementation and maintenance (3rd ed.). Earthscan.

Chicago-tyylinen lähdeviittaus

Christopher Sheldon. Environmental Management Systems: Step by Step Guide to Implementation and Maintenance. 3rd ed. London: Earthscan, 2007.

MLA-viite

Christopher Sheldon. Environmental Management Systems: Step by Step Guide to Implementation and Maintenance. 3rd ed. Earthscan, 2007.