APA-referens

Spencer, E. W. (2003). Earth science: Understanding environmental systems. Boston: McGraw-Hill.

Chicago-stil citat

Spencer, Edgar W. Earth Science: Understanding Environmental Systems. Boston: McGraw-Hill, 2003.

MLA-referens

Spencer, Edgar W. Earth Science: Understanding Environmental Systems. Boston: McGraw-Hill, 2003.

Varning: dessa hänvisningar är inte alltid fullständigt riktiga.