RT Journal Article SR Electronic T1 Pulmonary rehabilitation in chronic respiratory insufficiency. 1. Pulmonary rehabilitation in perspective: historical roots, present status, and future projections. JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 855 OP 862 DO 10.1136/thx.48.8.855 VO 48 IS 8 A1 T L Petty YR 1993 UL http://thorax.bmj.com/content/48/8/855.abstract AB