TY  - RPRT
TI  - Upper-gastrointestinal endoscopy in perspective.
AU  - R H Salter
PY  - 1975
DO  - 10.1016/s0140-6736(75)90247-0
UR  - https://pubmed.ncbi.nlm.nih.gov/53341/
ID  - 53341
ER  -