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Submitted on: 17 March 2009.
Revised on: 03 July 2009.
Accepted on: 28 July 2009.
___________________AGRICULTURAL ECONOMICS---WILEY
Submitted on: 13 January 2017.
Revised on: 23 February 2017.
Accepted on: 01 April 2017.
___________________AGRICULTURAL ECONOMICS---WILEY
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