Author/Authors :
Mammadova, Gamar , El Zein, Fouad Institut de Math´ematiques de Jussieu, France , Langevin, Remi Universit´e de Bourgogne, France , Narmanov, Abdigappar National University of Uzbekistan, Uzbekistan , Soleev, Ahmadjon Samarkand State University, Uzbekistan
