Klemperer, W. David
McGraw-Hill, 1996
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Krott, Max
Springer, 2005
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Hyde, William F.
World Bank, 1991
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Slamet Rosyadi
Faculty of Social and Political Sciences, Universitas Jenderal Sudirman, Porwokerto, 2012
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Rutherfurd, Edward
Ballantine Books, 2000
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