1. Trakia University, Faculty of Medicine, Stoyan Kirkovich University Hospital, Department of Diagnostic Imaging, Department of Medical Physics, Biophysics, Roentgenology and Radiology, Stara Zagora, Bulgaria
2. Trakia University, Faculty of Medicine, Stoyan Kirkovich University Hospital, Clinic of Thoracic Surgery, Department of Special Surgery / Thoracic Surgery, Vascular Surgery, Pediatric Surgery and Orthopedics and Traumatology, Stara Zagora, Bulgaria