1. Department of Mathematics, University of Azad Jammu & Kashmir, Muzaffarabad 13100, Pakistan
2. Department of Mathematics & Statistics, Jordan University of Science and Technology, Irbid 22110, Jordan
3. Department of Mathematics, College of Science Al-Zulfi, Majmaah University, Al-Majmaah 11952, Saudi Arabia
4. Department of Mathematics, COMSATS University Islamabad, Sahiwal 57000, Pakistan