TY - JOUR T1 - Contemporary Ophthalmology JF - British Journal of Ophthalmology JO - Br J Ophthalmol SP - 522 LP - 522 DO - 10.1136/bjo.57.7.522-c VL - 57 IS - 7 A2 - , Y1 - 1973/07/01 UR - http://bjo.bmj.com/content/57/7/522.4.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -