RT Journal Article SR Electronic T1 Differences in disability as measured by the Health Assessment Questionnaire between patients with and without digital ulcers in systemic sclerosis: a post hoc analysis of pooled data from two randomised controlled trials in digital ulcers using bosentan JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 2055 OP 2056 DO 10.1136/ard.2009.122960 VO 69 IS 11 A1 Caleb Zelenietz A1 Janet Pope YR 2010 UL http://ard.bmj.com/content/69/11/2055.abstract AB