Submitted on: 26 August 2008.
Revised on: 29 September 2008.
Accepted on: 05 October 2008.
PUBLICATIONES MATHEMATICAE DEBRECEN
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Submitted on: 11 June 2011.
Revised on: 21 June 2011.
Accepted on: 15 July 2011.
PUBLICATIONES MATHEMATICAE DEBRECEN
Submitted on: 07 September 2022.
Revised on: 29 September 2022.
Accepted on: 14 October 2022.
PUBLICATIONES MATHEMATICAE DEBRECEN
Submitted on: 09 September 2011.
Revised on: 23 October 2011.
Accepted on: 01 November 2011.
PUBLICATIONES MATHEMATICAE DEBRECEN
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Submitted on: 30 August 2020.
Revised on: 09 September 2020.
Accepted on: 29 September 2020.
PUBLICATIONES MATHEMATICAE DEBRECEN
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