Submitted on: 31 October 2008.
Revised on: 13 November 2008.
Accepted on: 29 November 2008.
SIAM Journal on Applied Algebra and Geometry
Submitted on: 06 July 2011.
Revised on: 17 August 2011.
Accepted on: 07 September 2011.
SIAM Journal on Applied Algebra and Geometry
Submitted on: 28 September 2006.
Revised on: 12 October 2006.
Accepted on: 31 October 2006.
SIAM Journal on Applied Algebra and Geometry
Submitted on: 19 May 2013.
Revised on: 09 June 2013.
Accepted on: 24 June 2013.
SIAM Journal on Applied Algebra and Geometry
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