Submitted on: 29 January 1998.
Revised on: 21 February 1998.
Accepted on: 10 March 1998.
___________________International Journal of Mathematical Engineering and Management Sciences
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Submitted on: 23 September 2017.
Revised on: 16 November 2017.
Accepted on: 14 December 2017.
___________________International Journal of Mathematical Engineering and Management Sciences
Submitted on: 30 August 2006.
Revised on: 29 October 2006.
Accepted on: 14 December 2006.
___________________International Journal of Mathematical Engineering and Management Sciences
Submitted on: 04 October 2018.
Revised on: 26 December 2018.
Accepted on: 08 January 2019.
___________________International Journal of Mathematical Engineering and Management Sciences
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Submitted on: 21 July 2018.
Revised on: 11 November 2018.
Accepted on: 02 January 2019.
___________________International Journal of Mathematical Engineering and Management Sciences
Submitted on: 10 October 2000.
Revised on: 22 January 2001.
Accepted on: 14 March 2001.
___________________International Journal of Mathematical Engineering and Management Sciences
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