(Earth Works Group (U.S. (1989). 50 simple things you can do to save the earth. Earthworks Press.
Chicagoスタイル(17版)引用形式(Earth Works Group (U.S. 50 Simple Things You Can Do to Save the Earth. .Berkeley, CA: Earthworks Press, 1989.
MLA(9版)引用形式(Earth Works Group (U.S. 50 Simple Things You Can Do to Save the Earth. Earthworks Press, 1989.
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