Submitted on: 11 March 2023.
Revised on: 30 June 2023.
Accepted on: 15 July 2023.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
Submitted on: 01 November 2002.
Revised on: 26 January 2003.
Accepted on: 25 March 2003.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
Submitted on: 08 April 2000.
Revised on: 03 July 2000.
Accepted on: 26 August 2000.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
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