Submitted on: 27 January 2004.
Revised on: 31 March 2004.
Accepted on: 10 May 2004.
___________________AGRICULTURAL ECONOMICS---WILEY
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Submitted on: 01 October 2012.
Revised on: 20 November 2012.
Accepted on: 30 November 2012.
___________________AGRICULTURAL ECONOMICS---WILEY
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