1. Abdus Salam School of Mathematical Sciences, Government College University, Lahore 54600, Pakistan
2. Department of Mathematics, Government College University, Katchery Road, Lahore 54000, Pakistan
3. Department of Medical Research, China Medical University, Taichung 404, Taiwan
4. Department of Mathematics, Unaizah College of Sciences and Arts, Qassim University, Buraydah 52571, Saudi Arabia
5. Department of Mathematics, Faculty of Science, Sohag University, Sohag 82524, Egypt
6. Institute of Research and Development of Processes, Department of Electricity and Electronics, Faculty of Science and Technology, University of the Basque Country, 48940 Leioa, Spain