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Submitted on: 14 March 2016.
Revised on: 17 June 2016.
Accepted on: 07 July 2016.
___________________Decisions in Economics and Finance
Submitted on: 22 March 2001.
Revised on: 02 May 2001.
Accepted on: 28 May 2001.
___________________Decisions in Economics and Finance
Submitted on: 01 March 2015.
Revised on: 21 May 2015.
Accepted on: 12 June 2015.
___________________Decisions in Economics and Finance
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Submitted on: 27 March 2010.
Revised on: 15 May 2010.
Accepted on: 06 June 2010.
___________________Decisions in Economics and Finance
Submitted on: 04 February 2020.
Revised on: 17 May 2020.
Accepted on: 29 May 2020.
___________________Decisions in Economics and Finance
Submitted on: 01 January 2016.
Revised on: 19 April 2016.
Accepted on: 14 May 2016.
___________________Decisions in Economics and Finance
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