1. Department of History, University of Nottingham, University Park, Nottingham NG7 2RD, UK
2. School of Chemistry & Biosciences, Faculty of Life Sciences, University of Bradford, Bradford BD7 1DP, UK
3. Department of Archaeology, University of Ghent, Sint Pietersnieuwstraat 35, B-9000 Ghent, Belgium
4. Independent Researcher, Newark, Nottinghamshire NG24 1DZ, UK