http://reply.papertrans.cn/2/200/19973/19973-31.png
Submitted on: 21 November 2000.
Revised on: 12 January 2001.
Accepted on: 04 March 2001.
___________________JOURNAL OF TRANSPORT ECONOMICS AND POLICY
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Submitted on: 16 August 2005.
Revised on: 29 October 2005.
Accepted on: 16 December 2005.
___________________JOURNAL OF TRANSPORT ECONOMICS AND POLICY
http://reply.papertrans.cn/2/200/19973/19973-35.png
Submitted on: 07 October 2014.
Revised on: 18 January 2015.
Accepted on: 04 March 2015.
___________________JOURNAL OF TRANSPORT ECONOMICS AND POLICY