Submitted on: 27 September 2003.
Revised on: 06 January 2004.
Accepted on: 03 March 2004.
___________________European Actuarial Journal---SPRINGER HEIDELBERG
Submitted on: 17 July 2024.
Revised on: 25 September 2024.
Accepted on: 07 November 2024.
___________________European Actuarial Journal---SPRINGER HEIDELBERG
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http://reply.papertrans.cn/1/91/9022/9022-34.png
Submitted on: 28 August 2002.
Revised on: 03 October 2002.
Accepted on: 19 October 2002.
___________________European Actuarial Journal---SPRINGER HEIDELBERG
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