1. Blindness and visual impairment in an American urban population;Tielsch;Arch Ophthalmol,1990
2. Monocular visual acuity of persons 4-74 years, United States, 1971-1972;Roberts,1977
3. The Beaver Dam Eye Study: visual acuity;Klein;Ophthalmology,1991
4. Aging in the eighties, impaired senses for sound and light in persons age 65 years and over. Preliminary data from the Supplement on Aging to the National Health Interview Survey: United States, January-June 1984;Havlik,1986
5. The Framingham Eye Study Monograph;Liebowitz;Surv Ophthalmol,1980