1. Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamil Nadu, India; Department of Mathematics and Applied Mathematics, University of Johannesburg, Auckland Park 2006, South Africa, E-mail: drhknashine@gmail.com, hemant.nashine@vit.ac.in
2. Informetrics Research Group, Ton 1Duc Thang University, Ho Chi Minh City, Vietnam and Faculty of Mathematics & Statistics, Ton Duc Thang University, Ho Chi Minh City, Vietnam, E-mail: rabhaibrahim@tdtu.edu.vn
3. Department of Mathematics, Texas A & M University - Kingsville, TX, USA, E-mail: ravi.agarwal@tamuk.edu and Distinguished University Professor of Mathematics, Florida Institute Of Technology, Melbourne, FL 32901, USA