PT - JOURNAL ARTICLE ED - , TI - Proceedings of the Thoracic Society AID - 10.1136/thx.34.5.692 DP - 1979 Oct 01 TA - Thorax PG - 692--709 VI - 34 IP - 5 4099 - http://thorax.bmj.com/content/34/5/692.short 4100 - http://thorax.bmj.com/content/34/5/692.full SO - Thorax1979 Oct 01; 34