1. A simple method of testing for color-blindness Author(s): Sewall, Henry, 1855-1936, author Publication: [Philadelphia?] : [publisher not identified], [1886?] Subject(s): Color Vision Defects -- diagnosisColor Perception Tests
2. A new series of Berlin wools for the scientific detection of subnormal color-perception (color-blindness) Author(s): Oliver, Charles A. (Charles Augustus), 1853-1911 author Publication: [Philadelphia?] : [publisher not identified], [1886?] Subject(s): Color Vision Defects -- diagnosisColor Perception TestsWool