The liberation of the serfs: the economics of unfree labor
Jurgen Georg Backhaus, editor
[Springer, Springer], 2012
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Sellin, J. Thorsten
Slavery and the penal system
Elsevier, 1976
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Washington, Booker T.
Up from slavery: an autobiography
Oxford University Press, 1900
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Russell, Richard Joel
Culture worlds
Macmillan, 1954, 1951
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Russell, Richard Joel
Culture worlds
Macmillan, 1958
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