Submitted on: 13 March 2014.
Revised on: 19 April 2014.
Accepted on: 20 May 2014.
___________________JOURNAL OF AGRICULTURAL ECONOMICS
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Submitted on: 12 April 2002.
Revised on: 03 August 2002.
Accepted on: 01 September 2002.
___________________JOURNAL OF AGRICULTURAL ECONOMICS
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