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Submitted on: 18 September 2016.
Revised on: 28 November 2016.
Accepted on: 22 December 2016.
___________________ADVANCES IN APPLIED PROBABILITY
Submitted on: 19 August 2001.
Revised on: 03 December 2001.
Accepted on: 23 January 2002.
___________________ADVANCES IN APPLIED PROBABILITY
Submitted on: 16 October 2013.
Revised on: 12 January 2014.
Accepted on: 28 January 2014.
___________________ADVANCES IN APPLIED PROBABILITY
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