1. Department of Mathematics, Quaid-i-Azam University Islamabad, Islamabad, Pakistan
2. Department of Mathematics, Women University of Azad Jammu and Kashmir, Bagh, Pakistan
3. Institut Supérieur d’Informatique et des Techniques de Communication, Université de Sousse, 4000 H. Sousse, Tunisia
4. China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
5. Department of Mathematics and Applied Mathematics, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa
6. Quantum Leap Africa (QLA), AIMS Rwanda Centre, Remera Sector KN 3, Kigali, Rwanda
7. African Center for Advanced Studies, P.O. Box 4477, Yaounde, Cameroon