1. Department of Mathematics, The University of Faisalabad, Faisalabad, Pakistan
2. Department of Mathematics and Statistics, FBAS, International Islamic University Islamabad, Islamabad, Pakistan
3. College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao, China
4. School of Mines, China University of Mining and Technology, Xuzhou, Jiangsu, China
5. Department of Mathematics and Statistics, Bacha Khan University, Charsadda, Pakistan