Submitted on: 07 February 2005.
Revised on: 16 March 2005.
Accepted on: 06 May 2005.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
Submitted on: 24 January 2009.
Revised on: 18 February 2009.
Accepted on: 11 April 2009.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
Submitted on: 18 March 2007.
Revised on: 31 May 2007.
Accepted on: 11 June 2007.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
Submitted on: 08 April 2009.
Revised on: 23 July 2009.
Accepted on: 25 August 2009.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
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Submitted on: 18 June 2016.
Revised on: 14 September 2016.
Accepted on: 12 November 2016.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
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Submitted on: 03 October 2011.
Revised on: 07 December 2011.
Accepted on: 25 December 2011.
___________________ALEA-Latin American Journal of Probability and Mathematical Statistics
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