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Submitted on: 19 August 2002.
Revised on: 15 September 2002.
Accepted on: 10 October 2002.
Research in Mathematics
Submitted on: 24 October 2016.
Revised on: 16 November 2016.
Accepted on: 22 November 2016.
Research in Mathematics---TAYLOR & FRANCIS LTD
Submitted on: 11 November 2019.
Revised on: 19 November 2019.
Accepted on: 06 December 2019.
Research in Mathematics
Submitted on: 04 November 2002.
Revised on: 16 November 2002.
Accepted on: 05 December 2002.
Research in Mathematics---TAYLOR & FRANCIS LTD
Submitted on: 12 July 2019.
Revised on: 22 July 2019.
Accepted on: 04 August 2019.
Research in Mathematics---TAYLOR & FRANCIS LTD
Submitted on: 16 March 2021.
Revised on: 28 March 2021.
Accepted on: 16 April 2021.
Research in Mathematics
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