Stigler, George J.
Trends in employment in the service industries
Princeton University Press, 1956
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Clawson, Marion
America's land and its uses
John Hopkins, 1972
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Indonesian Youth Employment: Trends and Consequences
Journal of Population, 8 (1) 2002 : 23-72, 2002
Artikel Jurnal
Future trends in Indonesian mineral exploration
Artikel Jurnal
Linfield, Robert F.
Telecommunications: present status and future trends
Noyes Data, 1995
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