Submitted on: 28 October 2009.
Revised on: 30 December 2009.
Accepted on: 29 January 2010.
___________________Economic Systems---ELSEVIER
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Submitted on: 07 May 2022.
Revised on: 27 May 2022.
Accepted on: 06 July 2022.
___________________Economic Systems---ELSEVIER
Submitted on: 19 November 2017.
Revised on: 20 January 2018.
Accepted on: 07 February 2018.
___________________Economic Systems---ELSEVIER
Submitted on: 17 June 2019.
Revised on: 08 September 2019.
Accepted on: 08 October 2019.
___________________Economic Systems---ELSEVIER
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Submitted on: 11 April 2019.
Revised on: 25 July 2019.
Accepted on: 01 September 2019.
___________________Economic Systems---ELSEVIER
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Submitted on: 17 March 2003.
Revised on: 27 May 2003.
Accepted on: 26 June 2003.
___________________Economic Systems---ELSEVIER