1. Department of Continuing Education, Kellogg College, University of Oxford, 60-62 Banbury Road, Oxford OX2 6PN, UK
2. Department of Primary Care Health Sciences, University of Oxford, New Radcliffe House, Walton Street, Jericho OX2 6NW, UK
3. Bodleian Health Care Libraries, University of Oxford, Old Road, Headington OX3 7LE, UK