1. Collinson Jones Consulting, 56 Shropshire Street, Market Drayton, Shropshire TF9 3DD, UK
2. Blackbourn Geoconsulting, 4 Coltbridge Avenue, Edinburgh EH 12 6AH, UK
3. Geology Department, University of Keele, Keele, Staffordshire ST5 5BG, UK
4. Intera Information Technologies (UK) Ltd, Highlands Farm, Greys Road, Henley-on-Thames, Oxfordshire RG9 4PS, UK