RT Journal Article SR Electronic T1 Beiträge zur Rheumatologie JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 544 OP 544 DO 10.1136/ard.30.5.544-a VO 30 IS 5 A1 David Preiskel YR 1971 UL http://ard.bmj.com/content/30/5/544.1.abstract AB