1. University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia + Oncology Institute of Vojvodina, Sremska Kamenica, Serbia
2. University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia + Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia
3. Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia
4. University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia