World Resources Institute. (1993). The 1993 Information please environmental almanac. Houghton Mifflin Co.
Chicago Style aipamenaWorld Resources Institute. The 1993 Information Please Environmental Almanac. Boston: Houghton Mifflin Co, 1993.
MLA aipamenaWorld Resources Institute. The 1993 Information Please Environmental Almanac. Houghton Mifflin Co, 1993.
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