Submitted on: 27 January 2000.
Revised on: 22 March 2000.
Accepted on: 16 May 2000.
___________________JOURNAL OF POPULATION RESEARCH
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Submitted on: 16 April 1999.
Revised on: 09 July 1999.
Accepted on: 12 August 1999.
___________________JOURNAL OF POPULATION RESEARCH
Submitted on: 24 December 2015.
Revised on: 03 February 2016.
Accepted on: 17 February 2016.
___________________JOURNAL OF POPULATION RESEARCH
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Submitted on: 17 July 2011.
Revised on: 07 August 2011.
Accepted on: 03 October 2011.
___________________JOURNAL OF POPULATION RESEARCH
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http://reply.papertrans.cn/2/189/18864/18864-28.png
Submitted on: 20 June 2020.
Revised on: 11 September 2020.
Accepted on: 21 October 2020.
___________________JOURNAL OF POPULATION RESEARCH
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