1. Department of Mathematics, Islamia College University Peshawar, Peshawar, Pakistan; gulrahmat@icp.edu.pk; tariqshahmaths@gmail.com
2. Department of Mathematics, University of Malakand, Chakdara Dir(L), Khyber Pakhtunkhwa, Pakistan
3. Department of Mathematics, Umm Al-Qura University, Faculty of Applied sciences, P. O. Box 14035, Holly Makkah 21955, Saudi Arabia; samansour@uqu.edu.sa
4. Université de Sousse, Institut Supérieur d'Informatique et des Techniques de Communication, H. Sousse 4000, Tunisia
5. China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
6. Department of Mathematics and Applied Mathematics, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa