The Earth Works Group. (1989). 50 simple things you can do to save the earth. Berkeley, CA: Earthworks Press.
Trích dẫn kiểu ChicagoThe Earth Works Group. 50 Simple Things You Can Do to Save the Earth. Berkeley, CA: Earthworks Press, 1989.
Deismireacht MLAThe Earth Works Group. 50 Simple Things You Can Do to Save the Earth. Berkeley, CA: Earthworks Press, 1989.
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