1. Department of Thoracic Surgery, Teaching Hospital Hassan II, Fez, Morocco
2. Department of Cardiovascular Surgery, Teaching Hospital Hassan II, Fez, Morocco
3. Department of Stomatology and Maxillofacial Surgery, Hôpital Général de Référence, Niamey, Niger
4. Department of Surgery and Surgical Specialities, Faculty of Health Sciences, Abdou Moumouni University, Niamey, Niger
5. Department of Surgery, Faculty of Medicine and Pharmacy, University Sidi Mohamed Ben Adellah, Fez, Morocco
6. Department of General Surgery, National Hospital of Niamey, Niamey, Niger
7. Department of Pediatric Surgery, Hospital Amirou Boubacar Diallo, Niamey, Niger