1. Department of Otorhinolaryngology, National Memorial Hospital Vukovar, Vukovar, Croatia
2. Department of Otorhinolaryngology Neurosurgery and Radiology, Faculty of Dental Medicine and Health, “Josip Juraj Strossmayer University” of Osijek, Osijek, Croatia
3. Department of Otorhinolaryngology and Head and Neck Surgery, University of Zagreb School of Medicine, University Hospital Center “Sisters of Mercy”, Zagreb, Croatia
4. Department of ENT Head and Neck Surgery, General Hospital “Dr. Josip Benčević”, Slavonski Brod, Croatia
5. Department of Otorhinolaryngology and Head and Neck Surgery, Clinical Hospital Centre Osijek, Osijek, Croatia