TY  - RPRT
TI  - Letter: Upper-gastrointestinal endoscopy.
AU  - D G Colin-Jones
PY  - 1975
DO  - 10.1016/s0140-6736(75)90346-3
UR  - https://pubmed.ncbi.nlm.nih.gov/53539/
ID  - 53539
ER  -