Submitted on: 25 August 2023.
Revised on: 05 December 2023.
Accepted on: 07 January 2024.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
Submitted on: 28 April 2009.
Revised on: 10 June 2009.
Accepted on: 24 July 2009.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
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Submitted on: 18 July 2020.
Revised on: 15 October 2020.
Accepted on: 12 December 2020.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
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Submitted on: 13 November 2019.
Revised on: 13 February 2020.
Accepted on: 07 April 2020.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
Submitted on: 04 April 2013.
Revised on: 04 May 2013.
Accepted on: 07 June 2013.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
Submitted on: 08 March 2010.
Revised on: 15 April 2010.
Accepted on: 01 May 2010.
___________________ACTA MATHEMATICA HUNGARICA---SPRINGER
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