United Nations Environment Programme & UNEP. Global Environment Outlook 3: Past, present and future perspectives. GEO-3: past, present and future perspectives.
Chicago-viite (17. p.)United Nations Environment Programme ja UNEP. Global Environment Outlook 3: Past, Present and Future Perspectives. GEO-3: Past, Present and Future Perspectives. UNEP. EARTHSCAN.
MLA-viite (9. p.)United Nations Environment Programme ja UNEP. Global Environment Outlook 3: Past, Present and Future Perspectives. GEO-3: Past, Present and Future Perspectives.
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