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Submitted on: 03 January 2008.
Revised on: 23 February 2008.
Accepted on: 04 April 2008.
___________________Applied Economic Perspectives and Policy
Submitted on: 19 August 2002.
Revised on: 22 September 2002.
Accepted on: 06 November 2002.
___________________Applied Economic Perspectives and Policy
Submitted on: 08 October 2000.
Revised on: 11 November 2000.
Accepted on: 03 December 2000.
___________________Applied Economic Perspectives and Policy
Submitted on: 13 May 2003.
Revised on: 08 June 2003.
Accepted on: 07 July 2003.
___________________Applied Economic Perspectives and Policy
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