RT Journal Article SR Electronic T1 Painful Horner syndrome JF Postgraduate Medical Journal JO Postgrad Med J FD The Fellowship of Postgraduate Medicine SP 142 OP 142 DO 10.1136/pgmj.2007.062497 VO 84 IS 989 A1 P Wilkerson A1 D Sarma A1 J Derodra YR 2008 UL http://pmj.bmj.com/content/84/989/142.abstract AB