Submitted on: 02 February 2015.
Revised on: 26 February 2015.
Accepted on: 31 March 2015.
___________________Annals of Economics and Finance
Submitted on: 11 July 2012.
Revised on: 02 October 2012.
Accepted on: 24 November 2012.
___________________Annals of Economics and Finance
Submitted on: 16 June 2005.
Revised on: 18 July 2005.
Accepted on: 25 August 2005.
___________________Annals of Economics and Finance
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Submitted on: 10 May 2005.
Revised on: 04 July 2005.
Accepted on: 24 July 2005.
___________________Annals of Economics and Finance
Submitted on: 09 September 1998.
Revised on: 18 October 1998.
Accepted on: 29 November 1998.
___________________Annals of Economics and Finance