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Submitted on: 15 July 2003.
Revised on: 29 October 2003.
Accepted on: 26 November 2003.
___________________Journal of Agricultural and Applied Economics
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Submitted on: 19 October 1998.
Revised on: 24 November 1998.
Accepted on: 22 December 1998.
___________________Journal of Agricultural and Applied Economics
Submitted on: 22 February 2010.
Revised on: 10 May 2010.
Accepted on: 29 June 2010.
___________________Journal of Agricultural and Applied Economics
Submitted on: 18 July 2014.
Revised on: 28 September 2014.
Accepted on: 25 November 2014.
___________________Journal of Agricultural and Applied Economics
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Submitted on: 14 February 2006.
Revised on: 23 March 2006.
Accepted on: 04 April 2006.
___________________Journal of Agricultural and Applied Economics