Submitted on: 11 April 2004.
Revised on: 17 June 2004.
Accepted on: 03 August 2004.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
http://reply.papertrans.cn/1/19/1856/1856-32.png
Submitted on: 11 July 2018.
Revised on: 27 September 2018.
Accepted on: 18 November 2018.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
http://reply.papertrans.cn/1/19/1856/1856-34.png
Submitted on: 05 November 2022.
Revised on: 03 January 2023.
Accepted on: 06 February 2023.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER
Submitted on: 12 April 2004.
Revised on: 04 August 2004.
Accepted on: 23 August 2004.
___________________ANNALS OF REGIONAL SCIENCE---SPRINGER