(1981). An Environmental bibliography: Publications issued by unep or under its auspices 1973-1980. United Nations Environment Programme.
Chicago-viite (17. p.)An Environmental Bibliography: Publications Issued by Unep or Under Its Auspices 1973-1980. Nairobi: United Nations Environment Programme, 1981.
MLA-viite (9. p.)An Environmental Bibliography: Publications Issued by Unep or Under Its Auspices 1973-1980. United Nations Environment Programme, 1981.
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