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Submitted on: 11 July 2010.
Revised on: 22 August 2010.
Accepted on: 14 September 2010.
Mathematics Enthusiast
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Submitted on: 04 October 2009.
Revised on: 16 November 2009.
Accepted on: 10 December 2009.
Mathematics Enthusiast
Submitted on: 20 February 2018.
Revised on: 05 March 2018.
Accepted on: 14 March 2018.
Mathematics Enthusiast
Submitted on: 22 March 1998.
Revised on: 20 April 1998.
Accepted on: 14 May 1998.
Mathematics Enthusiast---UNIV MONTANA, DEPT MATHEMATICAL SCIENCES
Submitted on: 17 May 1999.
Revised on: 06 June 1999.
Accepted on: 01 July 1999.
Mathematics Enthusiast
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