1. Faculty of Engineering; Nottingham Geospatial Institute; Innovation Park, Jubilee Campus Nottingham NG7 2TU UK
2. Department of Geography; University of Leicester; Leicester LE1 7RH UK
3. Geography Department; Qassim University; Box 1343 Saudi Arabia
4. Institute of Arab and Islamic Studies, College of Social Sciences and International Studies; University of Exeter; Exeter Devon EX4 4ND UK