1. University Hospital Wales; Department of Surgery; Cardiff Wales UK CF14 4XW
2. University Hospital North Tees; Colorectal Surgery; Hardwick Stockton on Tees Teesside UK TS19 8PE
3. Bispebjerg Hospital; Department of Surgical Gastroenterology K; Bispebjerg Bakke 23 Copenhagen NV Denmark DK-2400
4. Aarhus University Hospital; Department of Surgery; Aarhus Denmark 8000