Submitted on: 04 November 2012.
Revised on: 19 January 2013.
Accepted on: 09 March 2013.
___________________AGRICULTURAL ECONOMICS---WILEY
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Submitted on: 24 June 2018.
Revised on: 10 October 2018.
Accepted on: 25 November 2018.
___________________AGRICULTURAL ECONOMICS---WILEY
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Submitted on: 23 January 1999.
Revised on: 06 April 1999.
Accepted on: 09 May 1999.
___________________AGRICULTURAL ECONOMICS---WILEY
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