1. Department of Mathematics and Statistics, International Islamic University, Islamabad, Pakistan
2. Department of Mathematics, Faculty of Arts and Science, Yildiz Technical University, Esenler, 34210 Istanbul, Turkey
3. Department of Mathematics, Quaid-e-Azam University, Islamabad, Pakistan
4. Quantum Leap Africa (QLA) AIMS Rwanda Center, Remera Sector KN 3, Kigali, Rwanda
5. Institut de Mathématiques et de Sciences Physiques (IMSP/UAC), Laboratoire de Topologie Fondamentale, Computationnelle et leurs Applications (Lab-ToFoCApp), BP 613 Porto-Novo, Benin
6. African Center for Advanced Studies, P.O. Box 4477, Yaounde, Cameroon