RT Journal Article SR Electronic T1 Retinal branch vein occlusion. Changes at the site of obstruction. JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 548 OP 554 DO 10.1136/bjo.58.5.548 VO 58 IS 5 A1 R S Clemett YR 1974 UL http://bjo.bmj.com/content/58/5/548.abstract AB