1. Department of Mathematics, Usto University, Oran, Algeria
2. Department of Mathematics and Computer Science, University of Bechar, Bechar, Algeria
3. Near East University, Operational Research Center in Healthcare, Nicosia/Mersin, Turkey + Section of Mathematics, International Telematic University Uninettuno, Corso Vittorio Emanuele II, Roma, Italy
4. Renewable Energy Research Centre, Department of Teacher Training in Electrical Engineering, Faculty of Technical Education, King Mongkut’s University of Technology North Bangkok, Bangsue, Bangkok Thailand