http://reply.papertrans.cn/1/80/7961/7961-21.png
Submitted on: 18 January 2006.
Revised on: 04 March 2006.
Accepted on: 03 April 2006.
___________________Economics & Human Biology---ELSEVIER
http://reply.papertrans.cn/1/80/7961/7961-23.png
http://reply.papertrans.cn/1/80/7961/7961-24.png
http://reply.papertrans.cn/1/80/7961/7961-25.png
Submitted on: 17 June 2022.
Revised on: 07 August 2022.
Accepted on: 02 October 2022.
___________________Economics & Human Biology---ELSEVIER
http://reply.papertrans.cn/1/80/7961/7961-27.png
Submitted on: 06 May 2012.
Revised on: 09 August 2012.
Accepted on: 17 September 2012.
___________________Economics & Human Biology---ELSEVIER
http://reply.papertrans.cn/1/80/7961/7961-29.png
http://reply.papertrans.cn/1/80/7961/7961-30.png