PT - JOURNAL ARTICLE AU - GD Summers TI - Reply AID - 10.1136/thx.36.5.400-a DP - 1981 May 01 TA - Thorax PG - 400--400 VI - 36 IP - 5 4099 - http://thorax.bmj.com/content/36/5/400.2.short 4100 - http://thorax.bmj.com/content/36/5/400.2.full SO - Thorax1981 May 01; 36