TY - JOUR T1 - AUTHORS' REPLY JF - Thorax JO - Thorax SP - 1169 LP - 1169 DO - 10.1136/thx.51.11.1169 VL - 51 IS - 11 AU - Peter Ormerod Y1 - 1996/11/01 UR - http://thorax.bmj.com/content/51/11/1169.1.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -