1. Abdus Salam School of Mathematical Sciences, Government College University, 68-B, New Muslim Town, Lahore 54600, Pakistan
2. Department of Mechanical Engineering Sciences, Faculty of Engineering and the Built Environment, Doornfontein Campus, University of Johannesburg, Johannesburg 2092, South Africa
3. Department of Medical Research, China Medical University, Taichung 406040, Taiwan
4. Department of Mathematics, “1 Decembrie 1918” University of Alba Iulia, 510009 Alba Iulia, Romania
5. Department of Mathematics, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, Romania