1. Department of Mathematical Sciences, Loughborough University, Loughborough LE11 3TU, United Kingdom
2. Faculty of Health, Engineering and Sciences, University of Southern Queensland, Toowoomba, QLD 4350, Australia
3. Department of Applied Mathematics, Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Nizhny Novgorod 603950, Russia