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Submitted on: 03 March 2013.
Revised on: 09 April 2013.
Accepted on: 17 April 2013.
RAND JOURNAL OF ECONOMICS
Submitted on: 30 October 2000.
Revised on: 20 November 2000.
Accepted on: 11 December 2000.
RAND JOURNAL OF ECONOMICS---WILEY
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