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Submitted on: 12 March 2001.
Revised on: 03 May 2001.
Accepted on: 09 June 2001.
___________________JOURNAL OF AGRICULTURAL AND RESOURCE ECONOMICS
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Submitted on: 19 February 1998.
Revised on: 16 May 1998.
Accepted on: 22 June 1998.
___________________JOURNAL OF AGRICULTURAL AND RESOURCE ECONOMICS
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Submitted on: 12 December 2001.
Revised on: 18 January 2002.
Accepted on: 14 March 2002.
___________________JOURNAL OF AGRICULTURAL AND RESOURCE ECONOMICS
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Submitted on: 16 June 2007.
Revised on: 01 October 2007.
Accepted on: 18 October 2007.
___________________JOURNAL OF AGRICULTURAL AND RESOURCE ECONOMICS