Submitted on: 19 March 2010.
Revised on: 20 May 2010.
Accepted on: 04 July 2010.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
Submitted on: 22 October 2004.
Revised on: 03 January 2005.
Accepted on: 24 February 2005.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
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Submitted on: 13 June 2008.
Revised on: 16 September 2008.
Accepted on: 01 October 2008.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
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http://reply.papertrans.cn/1/76/7552/7552-26.png
Submitted on: 15 December 1999.
Revised on: 27 January 2000.
Accepted on: 18 February 2000.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
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Submitted on: 23 October 2016.
Revised on: 29 December 2016.
Accepted on: 20 February 2017.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
Submitted on: 05 September 2018.
Revised on: 23 November 2018.
Accepted on: 03 December 2018.
___________________DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE