Perry, J. S. (1996). Understanding our planet: An overview of the major scientific activities of ICSU and its partners that address global environmental change (Second edition.). International Council of Scientific Unions.
Chicago-referens (17:e uppl.)Perry, John S. Understanding Our Planet: An Overview of the Major Scientific Activities of ICSU and Its Partners That Address Global Environmental Change. Second edition. Paris, France: International Council of Scientific Unions, 1996.
MLA-referens (9:e uppl.)Perry, John S. Understanding Our Planet: An Overview of the Major Scientific Activities of ICSU and Its Partners That Address Global Environmental Change. Second edition. International Council of Scientific Unions, 1996.
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