TY - JOUR AU - Denzer, U; Beilenhoff, U; Eickhoff, A TI - S2k guideline: quality requirements for gastrointestinal endoscopy, AWMF registry no. 021-022 JO - Z Gastroenterol VL - 53 PY - 2015 L3 - PubMed-ID: 26447364 SP - E1 EP - E227 N1 - et al. ER -