1. Departamento de Ecuaciones Diferenciales y Análisis Numérico, Facultad de Matemáticas Universidad de Sevilla Seville Spain
2. Department of Statistics and Operations Research, College of Sciences King Saud University Riyadh Kingdom of Saudi Arabia
3. Department of Mathematics Faculty of Sciences of Sfax Sfax Tunisia
4. Department of Mathematics, Alkurmah University College Taif University Taif Saudi Arabia
5. Department of Mathematics, Sfax Preparatory Engineering Institute University of Sfax Sfax Tunisia