Submitted on: 26 October 2010.
Revised on: 05 December 2010.
Accepted on: 19 December 2010.
North American Actuarial Journal
Submitted on: 02 January 1999.
Revised on: 16 January 1999.
Accepted on: 03 February 1999.
North American Actuarial Journal
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Submitted on: 25 April 2005.
Revised on: 06 June 2005.
Accepted on: 25 June 2005.
North American Actuarial Journal