RT Journal Article SR Electronic T1 Accidental barium bronchography JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E670 OP E670 DO 10.1503/cmaj.160969 VO 189 IS 18 A1 Ahmad Zaheen A1 Matthew B. Stanbrook YR 2017 UL http://www.cmaj.ca/content/189/18/E670.abstract AB