Submitted on: 08 October 2018.
Revised on: 15 November 2018.
Accepted on: 29 November 2018.
Research in Mathematics
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Submitted on: 15 August 2009.
Revised on: 23 September 2009.
Accepted on: 09 October 2009.
Research in Mathematics
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Submitted on: 16 February 2007.
Revised on: 21 March 2007.
Accepted on: 17 April 2007.
Research in Mathematics---TAYLOR & FRANCIS LTD
Submitted on: 26 September 2022.
Revised on: 07 November 2022.
Accepted on: 01 December 2022.
Research in Mathematics---TAYLOR & FRANCIS LTD
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