Submitted on: 20 March 2019.
Revised on: 09 July 2019.
Accepted on: 28 August 2019.
___________________Economics and Finance Letters---CONSCIENTIA BEAM
Submitted on: 03 January 2003.
Revised on: 01 April 2003.
Accepted on: 22 April 2003.
___________________Economics and Finance Letters---CONSCIENTIA BEAM
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Submitted on: 22 March 2013.
Revised on: 02 May 2013.
Accepted on: 09 June 2013.
___________________Economics and Finance Letters---CONSCIENTIA BEAM
Submitted on: 28 January 2007.
Revised on: 08 May 2007.
Accepted on: 09 June 2007.
___________________Economics and Finance Letters---CONSCIENTIA BEAM
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Submitted on: 12 June 2010.
Revised on: 12 July 2010.
Accepted on: 14 August 2010.
___________________Economics and Finance Letters---CONSCIENTIA BEAM
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Submitted on: 27 March 2019.
Revised on: 16 May 2019.
Accepted on: 27 June 2019.
___________________Economics and Finance Letters---CONSCIENTIA BEAM