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Submitted on: 28 September 2007.
Revised on: 17 December 2007.
Accepted on: 27 January 2008.
___________________AFRICAN AFFAIRS---OXFORD UNIV PRESS
Submitted on: 16 July 2006.
Revised on: 30 October 2006.
Accepted on: 26 November 2006.
___________________AFRICAN AFFAIRS---OXFORD UNIV PRESS
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