TY - JOUR T1 - Reply JF - Thorax JO - Thorax SP - 479 LP - 479 DO - 10.1136/thx.39.6.479-a VL - 39 IS - 6 AU - MX Fitzgerald Y1 - 1984/06/01 UR - http://thorax.bmj.com/content/39/6/479.2.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -