1. Department of Gastrointestinal Surgery Telemark Hospital Trust Skien Norway
2. Department of Medicine Telemark Hospital Trust Skien Norway
3. Department of Surgery Fonna Hospital Trust Stord Norway
4. Intervention Center Oslo University Hospital ‐ Rikshospitalet Oslo Norway
5. Department of Faculty Surgery N2 I.M.Sechenov First Moscow State Medical University Moscow Russia
6. Department of Surgery N1 Yerevan State Medical University after M.Heratsi Yerevan Armenia