Dworkin, D.M. Environmental sciences in developing countries - ICSU 1974 - 70 - Land use Semi-arid regions Sub-humid regions River basin development National parks Nature reserves Human settlement = Environmental sciences in developing countries Standard No.: M Standard Tech. Report. No.: LCCN: B Nat. Bib. No.: 3062 Nat. Bib. Agency Control No.: 577.4 ENV Subjects--Topical Terms: Environmental Sciences Universal Decimal Class. No.: 577.4