1. Science and Technology for Defense Lab LR19DN01, CMR, Military Academy, Tunis, Tunisia, Military Aeronautical Specialities School, Sfax, Tunisia, Department of Mathematics, Faculty of Science, University of Sfax, Sfax, Tunisia
2. Department of Mathematics, Faculty of Science, University of El Manar, Tunis, Tunisia
3. Department of Mathematics, FSTH, Abdelmalek Essaadi University, Tétouan, Morocco
4. Faculty of Education, University of Ljubljana, Ljubljana, Slovenia, Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia, Institute of Mathematics, Physics and Mechanics, Ljubljana, Slovenia