1. University of Liverpool; Institute of Child Health; Alder Hey Children's Foundation Trust Eaton Road Liverpool Merseyside UK L12 2AP
2. Spaarne Hospital; Department of Paediatrics; Spaarnepoort 1 Hoofddorp Netherlands 2134 TM
3. Atrium Medical Centre; Department of Pediatrics; PO Box 4446 Heerlen Netherlands 6401 CX
4. Vrije Universiteit Medical Centre; Department of Paediatrics; P.O. Box 7057 De Boelelaan 117 Amsterdam Netherlands 1007 MB