Submitted on: 19 December 2007.
Revised on: 25 January 2008.
Accepted on: 10 March 2008.
___________________American Economic Journal-Applied Economics
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Submitted on: 12 December 2022.
Revised on: 17 January 2023.
Accepted on: 01 February 2023.
___________________American Economic Journal-Applied Economics
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Submitted on: 23 March 2006.
Revised on: 10 June 2006.
Accepted on: 04 July 2006.
___________________American Economic Journal-Applied Economics
Submitted on: 23 May 2001.
Revised on: 25 August 2001.
Accepted on: 15 October 2001.
___________________American Economic Journal-Applied Economics
Submitted on: 27 November 2009.
Revised on: 17 December 2009.
Accepted on: 06 February 2010.
___________________American Economic Journal-Applied Economics
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