Follow your professor's instruction for how to format your paper above all!
Making sense : a student's guide to research and writing : geography and environmental sciences / Margot Northey, David B. Knight, Dianne Draper
Making sense : a student's guide to research and writing : social sciences / Margot Northey, Lorne Tepperman
Environmental Studies professors use different citation styles depending on their sub-discipline and audience. Here are a few handy guides. If your style is not here, try searching the library catalog for a style guide.