Submitted on: 21 November 2008.
Revised on: 28 December 2008.
Accepted on: 20 February 2009.
___________________Flexible Services and Manufacturing Journal
Submitted on: 05 August 2003.
Revised on: 27 November 2003.
Accepted on: 14 January 2004.
___________________Flexible Services and Manufacturing Journal
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Submitted on: 25 February 1998.
Revised on: 12 April 1998.
Accepted on: 01 June 1998.
___________________Flexible Services and Manufacturing Journal
Submitted on: 26 November 1999.
Revised on: 06 March 2000.
Accepted on: 22 April 2000.
___________________Flexible Services and Manufacturing Journal
Submitted on: 08 November 2007.
Revised on: 23 February 2008.
Accepted on: 24 March 2008.
___________________Flexible Services and Manufacturing Journal
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