East, Roger
Profiles of people in power: the world's goverment leaders
Routledge, 2006
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Community leaders of the world / Published The American Bibliographical Institute
The American Bibliographical Institute, 1986
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Schuman, Frederick L.
International politics: the Western state system and the world community
McGraw-Hill, 1958
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Murphy, Robert F.
Robert H. Lowie
Columbia University Press, 1972
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The World in figures
editorial information compiled by the Economist
The Economist Newspaper Limited, 1984
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