Submitted on: 13 December 2018.
Revised on: 07 April 2019.
Accepted on: 03 May 2019.
___________________German Journal of Agricultural Economics
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Submitted on: 18 April 2009.
Revised on: 14 June 2009.
Accepted on: 11 August 2009.
___________________German Journal of Agricultural Economics
Submitted on: 22 September 2012.
Revised on: 13 October 2012.
Accepted on: 25 October 2012.
___________________German Journal of Agricultural Economics
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Submitted on: 12 October 1999.
Revised on: 24 November 1999.
Accepted on: 04 January 2000.
___________________German Journal of Agricultural Economics
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Submitted on: 02 June 2018.
Revised on: 06 August 2018.
Accepted on: 12 September 2018.
___________________German Journal of Agricultural Economics
Submitted on: 08 December 1998.
Revised on: 14 February 1999.
Accepted on: 28 February 1999.
___________________German Journal of Agricultural Economics