Gardiner, Gareth S.
21st century manager: meeting the challenges opportunities of the new corporate age
Peterso's, 1996
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Traffic congestion and traffic safety in the 21st century : challenges, innovations, and opportunities
American Society of Civil Engineers, 1997
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Bouvier, Leon F.
World population : challenges for the 21st century
Seven Lucks Press, 1999
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Southeast Asia : challenges of the 21st century / by Janadas Devan
Institute of Southeast Asia Studies , 1994
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"Challenges for the british library in the 21st century" Lynne Brindley
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