Report of an examination of railroad men for color blindness : read before the Pennsylvania State Medical Society, May 22nd, 1879

Keyser, Peter Dirck, 1835-1897, author · 1879 · [Philadelphia?] : [publisher not given] · 1 picture

Color Vision Defects -- diagnosis · Vision Screening · Railroads

Internet Archive · U.S. National Library of Medicine · Public domain (published before 1931)