RT Journal Article SR Electronic T1 Changes in Calibre of the Smaller Airways in Man JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 54 OP 58 DO 10.1136/thx.18.1.54 VO 18 IS 1 A1 Marshall, Robert A1 Holden, W. S. YR 1963 UL http://thorax.bmj.com/content/18/1/54.abstract AB