Submitted on: 26 April 1999.
Revised on: 22 May 1999.
Accepted on: 11 June 1999.
___________________International Journal of Quality and Service Sciences
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Submitted on: 11 September 2011.
Revised on: 27 November 2011.
Accepted on: 05 January 2012.
___________________International Journal of Quality and Service Sciences
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