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Submitted on: 24 June 2002.
Revised on: 16 August 2002.
Accepted on: 28 September 2002.
___________________Economics-The Open Access Open-Assessment E-Journal
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Submitted on: 17 August 2012.
Revised on: 23 September 2012.
Accepted on: 16 November 2012.
___________________Economics-The Open Access Open-Assessment E-Journal
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Submitted on: 08 January 2009.
Revised on: 18 March 2009.
Accepted on: 07 April 2009.
___________________Economics-The Open Access Open-Assessment E-Journal