Submitted on: 08 December 2000.
Revised on: 22 January 2001.
Accepted on: 22 March 2001.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH
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Submitted on: 31 July 2019.
Revised on: 20 November 2019.
Accepted on: 11 December 2019.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH
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Submitted on: 14 September 2013.
Revised on: 01 January 2014.
Accepted on: 26 February 2014.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH
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Submitted on: 30 December 2024.
Revised on: 30 January 2025.
Accepted on: 23 February 2025.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH
Submitted on: 02 August 2013.
Revised on: 17 November 2013.
Accepted on: 19 December 2013.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH
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Submitted on: 10 November 2005.
Revised on: 09 January 2006.
Accepted on: 11 February 2006.
___________________ADVANCES IN GEOMETRY---WALTER DE GRUYTER GMBH