Submitted on: 09 January 2024.
Revised on: 05 April 2024.
Accepted on: 20 April 2024.
___________________Journal of Geometry---SPRINGER BASEL AG
Submitted on: 16 November 2019.
Revised on: 21 January 2020.
Accepted on: 10 February 2020.
___________________Journal of Geometry---SPRINGER BASEL AG
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Submitted on: 26 June 1998.
Revised on: 30 September 1998.
Accepted on: 21 October 1998.
___________________Journal of Geometry---SPRINGER BASEL AG
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Submitted on: 04 April 2000.
Revised on: 04 May 2000.
Accepted on: 19 June 2000.
___________________Journal of Geometry---SPRINGER BASEL AG