RT Journal Article SR Electronic T1 ‘I'm useless after a bad night's sleep, doctor’: could sleep be the key to improving physical activity in people with COPD? JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 677 OP 678 DO 10.1136/thoraxjnl-2016-209905 VO 72 IS 8 A1 Emma H Baker A1 Daniel R Burrage YR 2017 UL http://thorax.bmj.com/content/72/8/677.abstract AB