1. Department for Respiratory Pathophysiology and Sleep Disordered Breathing, The Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia
2. Department of Internal Medicine, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
3. Pulmonary Department, University Clinical Centre Kragujevac, Kragujevac, Serbia
4. Department of Internal Medicine, Faculty of Medicine, University of Kragujevac, Kragujevac, Serbia
5. Department of Pneumonology Clinic for Pulmonology Diseases, University Clinical Centre of Serbia, Belgrade, Serbia
6. Department of Internal Medicine, School of Medicine, University of Belgrade, Serbia
7. Department for Asthma and Chronic Obstructive Pulmonary Diseases, Clinic for Lung Diseases, University Clinical Centre of Nis, Nis, Serbia
8. Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Serbia
9. Diagnostic-polyclinic Department, Clinic of Allergology and Immunology, University Clinical Center of Serbia
10. Department for Allergy and Obstructive Pulmonary Diseases, The Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia
11. Department of Nursing, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
12. Pulmonary Department, Clinical Hospital Centre Zemun, Belgrade, Serbia