RT Journal Article SR Electronic T1 Ventilation/Blood Flow and Gas Exchange JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 152 OP 152 DO 10.1136/thx.46.2.152-b VO 46 IS 2 A1 SE YR 1991 UL http://thorax.bmj.com/content/46/2/152.3.abstract AB