1. Department of Surgery, Caritas-Krankenhaus St. Josef, Regensburg,
2. Department of Surgery, Ospedale S. Maria degli Angeli, Pordenone
3. Academic Surgical Unit, St. James University Hospital, Leeds
4. Department of Surgery, Casa di Cura San Pio X, Milan Italy
5. Department of Proctology, Bagatelle-Maison de Sante, Talence-Cedex
6. Department of Digestive Surgery, University Hospital, Rouen France
7. Department of Surgery, Krankenhaus Waldfriede, Berlin Germany
8. Department of Surgery, Southampton General Hospital, Southampton United Kingdom
9. Department of Surgery, Notre-Dame, Charleroi, Belgium
10. Department of Surgery, Hospital Valle de Hebron, Barcelona, Spain
11. Department of Surgery, Kantonsspital, St. Gallen, Switzerland