Submitted on: 14 May 2001.
Revised on: 28 August 2001.
Accepted on: 10 October 2001.
___________________INFORMATION ECONOMICS AND POLICY
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Submitted on: 18 October 2021.
Revised on: 18 November 2021.
Accepted on: 15 January 2022.
___________________INFORMATION ECONOMICS AND POLICY
Submitted on: 01 February 2014.
Revised on: 15 April 2014.
Accepted on: 01 May 2014.
___________________INFORMATION ECONOMICS AND POLICY
Submitted on: 02 December 2020.
Revised on: 02 February 2021.
Accepted on: 14 February 2021.
___________________INFORMATION ECONOMICS AND POLICY
Submitted on: 07 May 2010.
Revised on: 14 July 2010.
Accepted on: 27 July 2010.
___________________INFORMATION ECONOMICS AND POLICY
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