Submitted on: 10 September 2004.
Revised on: 26 October 2004.
Accepted on: 15 November 2004.
___________________JOURNAL OF GEOMETRY AND PHYSICS
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Submitted on: 04 July 2000.
Revised on: 14 August 2000.
Accepted on: 28 August 2000.
___________________JOURNAL OF GEOMETRY AND PHYSICS
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Submitted on: 20 January 2025.
Revised on: 09 May 2025.
Accepted on: 28 June 2025.
___________________JOURNAL OF GEOMETRY AND PHYSICS
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