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Submitted on: 13 January 2000.
Revised on: 11 February 2000.
Accepted on: 17 February 2000.
North American Journal of Economics and Finance
Submitted on: 05 July 2001.
Revised on: 21 July 2001.
Accepted on: 06 August 2001.
North American Journal of Economics and Finance
Submitted on: 20 March 2014.
Revised on: 01 April 2014.
Accepted on: 09 April 2014.
North American Journal of Economics and Finance
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Submitted on: 16 November 2015.
Revised on: 12 December 2015.
Accepted on: 27 December 2015.
North American Journal of Economics and Finance
Submitted on: 07 October 2016.
Revised on: 26 October 2016.
Accepted on: 12 November 2016.
North American Journal of Economics and Finance
Submitted on: 07 December 1998.
Revised on: 23 December 1998.
Accepted on: 14 January 1999.
North American Journal of Economics and Finance
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