1. Clinic for Internal Medicine, University Clinical Hospital Center Bezanijska Kosa, 11000 Belgrade, Serbia
2. Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
3. Clinic of Cardiology, Clinical Center of Serbia, 11000 Belgrade, Serbia
4. Clinic for Internal Diseases Inter Medica, 18000 Nis, Serbia
5. School of Medicine, Singidunum University, 18000 Nis, Serbia
6. Clinic of Endocrinology, Diabetes and Metabolic Diseases, Clinical Center of Serbia, 11000 Belgrade, Serbia