1. Surgery Working Group, Society of Junior Doctors, Athens, Greece
2. Division of Pediatric Surgery, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
3. Department of Cardiothoracic Surgery, New York Presbyterian Medical Center, Weill Cornell College of Medicine, New York, NY, USA
4. Department of Obstetrics and Gynecology, Hospital of the University of Pennsylvania, Philadelphia, PA, USA