Anwar Ali Aldhafeeri, University of Sheffield, Sheffield, United Kingdom, Viktor Fedun, The University of Sheffield, Sheffield, United Kingdom, David B Jess, Queen's University Belfast, School of Mathematics and Physics, Belfast, United Kingdom, Wernher Brevis, Pontificia Universidad Catolica de Chile, Santiago, Chile and Gary Verth, University of Sheffield, School of Mathematics and Statistics, Sheffield, S10, United Kingdom