RT Journal Article SR Electronic T1 Normal and abnormal function of the diaphragm. JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 161 OP 163 DO 10.1136/thx.36.3.161 VO 36 IS 3 A1 P T Macklem YR 1981 UL http://thorax.bmj.com/content/36/3/161.abstract AB