1. Department of Mathematics, Veer Bahadur Singh Purvanchal University, Jaunpur, India
2. Department of Mathematics, Aden University, Aden, Yemen
3. Université de Sousse, Institut Supérieur d’Informatique et des Techniques de Communication, H. Sousse 4000, Tunisia
4. Department of Mathematics and Applied Mathematics, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa
5. China Medical University Hospital, China Medical University, Taichung 40402, Taiwan