Submitted on: 14 May 1998.
Revised on: 11 June 1998.
Accepted on: 07 July 1998.
Studies in Agricultural Economics
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Submitted on: 29 April 2014.
Revised on: 25 May 2014.
Accepted on: 11 June 2014.
Studies in Agricultural Economics
Submitted on: 14 June 1999.
Revised on: 01 July 1999.
Accepted on: 14 July 1999.
Studies in Agricultural Economics
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