WORLD Watch Institute. (2008). State of the world 2008: Innovations for a sustainable economy (25.).
シカゴスタイル引用形WORLD Watch Institute. State of the World 2008: Innovations for a Sustainable Economy. 25. Earth Scan London, 2008.
MLA引用形式WORLD Watch Institute. State of the World 2008: Innovations for a Sustainable Economy. 25. 2008.
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