1. University Children’s Hospital Ljubljana , Ljubljana Slovenia
2. Children’s Hospital Zagreb , Zagreb Croatia
3. University Children’s Hospital Bratislava , Bratislava Slovakia
4. Oncology Institute Cluj-Napoca , Cluj-Napoca Romania
5. Hematology Oncology Division, Department of Women’s and Children’s Health, University of Padova , Padova Italy
6. Faculty of Medicine, University of Ljubljana , Ljubljana , Slovenia