1. NGS, Science and Technology Facilities Council, Daresbury Laboratory, Warrington, Cheshire WA4 4AD, UK
2. OMII-UK, School of Electronics and Computer Science, University of Southampton, Highfield, Southampton SO17 1BJ, UK
3. Victorian eResearch Strategic Initiative (VeRSI), Melbourne, Victoria 3010, Australia
4. University of Sydney, Sydney, New South Wales 2006, Australia