Submitted on: 11 April 2022.
Revised on: 09 May 2022.
Accepted on: 02 June 2022.
___________________International Journal of Mathematics for Industry
Submitted on: 03 February 2018.
Revised on: 13 March 2018.
Accepted on: 23 April 2018.
___________________International Journal of Mathematics for Industry
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Submitted on: 29 January 1998.
Revised on: 19 February 1998.
Accepted on: 07 April 1998.
___________________International Journal of Mathematics for Industry
Submitted on: 26 May 2000.
Revised on: 03 July 2000.
Accepted on: 24 July 2000.
___________________International Journal of Mathematics for Industry
Submitted on: 26 November 2003.
Revised on: 18 December 2003.
Accepted on: 25 January 2004.
___________________International Journal of Mathematics for Industry
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