The author(s) of this article has(ve) requested that it be retracted from publication
Volume 9, Issue 1, November 2014, Pages 104–109




Soufiane Haddout1 and Mohamed Aghfir2
1 Department of Physics, Faculty of Science, Ibn Tofail University, B.P 242, 14000 Kénitra, Morocco
2 Department of Physics, Ecole Normale Superieure, B.P 2400, 40000 Marrakech, Morocco