TY - JOUR T1 - Failure of filtration operations in the African. JF - British Journal of Ophthalmology JO - Br J Ophthalmol SP - 594 LP - 598 DO - 10.1136/bjo.54.9.594 VL - 54 IS - 9 AU - N H Welsh Y1 - 1970/09/01 UR - http://bjo.bmj.com/content/54/9/594.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -