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Submitted on: 12 June 2011.
Revised on: 25 June 2011.
Accepted on: 04 July 2011.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
Submitted on: 27 June 2001.
Revised on: 03 August 2001.
Accepted on: 25 August 2001.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
Submitted on: 30 January 2007.
Revised on: 16 February 2007.
Accepted on: 04 March 2007.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
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Submitted on: 01 January 2013.
Revised on: 23 January 2013.
Accepted on: 30 January 2013.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
Submitted on: 15 May 1999.
Revised on: 20 June 1999.
Accepted on: 16 July 1999.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
Submitted on: 08 May 2017.
Revised on: 09 June 2017.
Accepted on: 06 July 2017.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
Submitted on: 11 June 2010.
Revised on: 19 June 2010.
Accepted on: 12 July 2010.
University Politehnica of Bucharest Scientific Bulletin-Series A-Applied Mathematics and Physics
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