Authors
Youssef Akdim
Department of Mathematics, Laboratory LAMA Faculty of Sciences, Fez, Morocco
Chakir Allalou
Sultan Moulay slimane University, Laboratory LMACS, Beni-Mellal, Morocco
© 2019 Youssef Akdim, Chakir Allalou, Abdelhafid Salmani, published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.