1. Department of Mathematics, Faculty of ScienceBenha University Benha Egypt
2. Department of Computational Mathematics and Computer ScienceInstitute of Natural Sciences and Mathematics, Ural Federal University Yekaterinburg Russia
3. Ural Branch of the Russian Academy of SciencesInstitute of Mathematics and Mechanics Yekaterinburg Russia
4. Departamento de Matemáticas y FísicaUniversidad Autónoma de Aguascalientes Aguascalientes Mexico