Submitted on: 16 April 2011.
Revised on: 02 June 2011.
Accepted on: 27 July 2011.
___________________International Journal of Economic Sciences
Submitted on: 15 July 2023.
Revised on: 20 September 2023.
Accepted on: 05 October 2023.
___________________International Journal of Economic Sciences
Submitted on: 17 November 2007.
Revised on: 22 December 2007.
Accepted on: 19 February 2008.
___________________International Journal of Economic Sciences
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