Submitted on: 06 July 2010.
Revised on: 22 July 2010.
Accepted on: 16 August 2010.
North American Actuarial Journal
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http://reply.papertrans.cn/3/233/23243/23243-23.png
Submitted on: 03 September 2020.
Revised on: 09 October 2020.
Accepted on: 23 October 2020.
North American Actuarial Journal
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Submitted on: 20 March 2014.
Revised on: 23 April 2014.
Accepted on: 02 May 2014.
North American Actuarial Journal
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Submitted on: 11 December 2019.
Revised on: 27 December 2019.
Accepted on: 21 January 2020.
North American Actuarial Journal