RT Journal Article SR Electronic T1 Puzzling Bronchial Trifurcation JF Respiratory Care FD American Association for Respiratory Care SP 1206 OP 1208 DO 10.4187/respcare.01200 VO 56 IS 8 A1 Boonsarngsuk, Viboon A1 Suwatanapongched, Thitiporn YR 2011 UL http://rc.rcjournal.com/content/56/8/1206.abstract AB