European Society of Gastrointestinal Endoscopy (ESGE) Guidelines: flexible enteroscopy for diagnosis and treatment of small-bowel diseases - Pohl, J.; Delvaux, M.; Ell, C.; Gay, G.; May, A.; Mulder, C. J. J.; Pennazio, M.; Perez-Cuadrado, E.; Vilmann, P. (Endoscopy, 2008)