RT Journal Article SR Electronic T1 Authors’ response: what determines which 6MWT is conventional? JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 86 OP 87 DO 10.1136/thoraxjnl-2014-206268 VO 70 IS 1 A1 Beekman, Emmylou A1 Mesters, Ilse A1 Gosselink, Rik A1 van Schayck, Onno C P A1 de Bie, Rob A YR 2015 UL http://thorax.bmj.com/content/70/1/86.2.abstract AB