1. Department of Dermatology, Churchill Hospital, Old Road, Headington, Oxford OX3 7LJ, U.K.
2. Department of Dermatology, Whittington Hospital, Magdala Avenue, London N19 5NF, U.K.
3. British Association of Dermatologists, Willan House, 4 Fitzroy Square, London W1T 5HQ, U.K.
4. York Hospital, Wigginton Road, York YO31 8HE, U.K.
5. Vrije Universtiteit, PO Box 7057, Amsterdam NL‐1007 MB, the Netherlands