1. Pediatric Hospital, University of the Saarland, Homburg, Germany
2. Department, of Pediatrics, University Hospital Essen, Germany
3. Institute of Transfusion Medicine and Immunology, Medical Faculty Mannheim, Germany
4. Department of Pediatric/Neonatology, University Medical Center, Maastricht, The Netherlands
5. Department of Neonatology, Erasmus MC-Sophia, Rotterdam, The Netherlands
6. Institute for Transfusion Medicine, University Hospital Essen, Germany