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Submitted on: 01 January 1998.
Revised on: 21 January 1998.
Accepted on: 02 February 1998.
Symmetry Integrability and Geometry-Methods and Applications
Submitted on: 24 July 2014.
Revised on: 29 August 2014.
Accepted on: 08 September 2014.
Symmetry Integrability and Geometry-Methods and Applications
Submitted on: 29 December 2020.
Revised on: 09 January 2021.
Accepted on: 15 January 2021.
Symmetry Integrability and Geometry-Methods and Applications
Submitted on: 07 May 2008.
Revised on: 07 June 2008.
Accepted on: 27 June 2008.
Symmetry Integrability and Geometry-Methods and Applications
Submitted on: 11 January 2009.
Revised on: 24 January 2009.
Accepted on: 13 February 2009.
Symmetry Integrability and Geometry-Methods and Applications
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