1. Serbian Medical Society, Academy of Medical Sciences, Belgrade, Serbia
2. University Children’s Hospital, Belgrade, Serbia + University of Belgrade, Faculty of Medicine, Belgrade, Serbia
3. University Children’s Hospital, Belgrade, Serbia
4. Valjevo Medical Centre, Valjevo, Serbia
5. Novi Pazar General Hospital, Novi Pazar, Serbia
6. University of Banja Luka, Faculty of Medicine, Republic of Srpska, Bosnia and Hezegovina