(Earth Works Group (U.S. (1989). 50 simple things you can do to save the earth. Earthworks Press.
Chicago (17e ed.) Bronvermelding(Earth Works Group (U.S. 50 Simple Things You Can Do to Save the Earth. .Berkeley, CA: Earthworks Press, 1989.
MLA (9e ed.) Bronvermelding(Earth Works Group (U.S. 50 Simple Things You Can Do to Save the Earth. Earthworks Press, 1989.
Let op: Deze citaties zijn niet altijd 100% accuraat.