1. Department of Mathematics, Malla Reddy Engineering College (Autonomous), Medchal Malkajgiri District, Secunderabad 500100, Hyderabad, India
2. Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632014, Tamil Nadu, India
3. Department of Mathematical Sciences, Federal Urdu University of Arts, Sciences & Technology, Gulshan-e-Iqbal Karachi 75300, Pakistan