1. Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK
2. Seismic Research Centre, The University of the West Indies, St. Augustine, Trinidad and Tobago
3. Montserrat Volcano Observatory, Flemmings, Montserrat, West Indies
4. CEDIAC Institute, Universidad Nacional de Cuyo, Argentina
5. Université de Paris, Institut de Physique du Globe de Paris, CNRS, F-75005 Paris, France
6. GNS Science, New Zealand
7. USRA, NASA-GSFC, Greenbelt, MD, USA