1. German Red Cross Blood Service Baden-Württemberg-Hessen, Institute of Transfusion Medicine and Immunohematology; Baden-Baden Germany
2. Institute of Transfusion Medicine and Immunology, Heidelberg University, Medical Faculty Mannheim, German Red Cross Blood Service Baden-Württemberg-Hessen; Mannheim Germany
3. Institute of Transfusion Medicine, University of Cologne; Cologne Germany
4. Bavarian Red Cross Blood Service; Munich Germany.