Submitted on: 26 April 2002.
Revised on: 12 August 2002.
Accepted on: 02 October 2002.
___________________International Journal of Sustainable Transportation
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Submitted on: 21 January 2007.
Revised on: 24 April 2007.
Accepted on: 23 May 2007.
___________________International Journal of Sustainable Transportation
Submitted on: 26 March 2015.
Revised on: 23 July 2015.
Accepted on: 15 September 2015.
___________________International Journal of Sustainable Transportation
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