1. On the anthrometric laboratory at the late International Health Exhibition;Galton;J. Anthrop. Inst.,1885
2. Relationships between age, visual acuity, and color vision;Chapanis;Human Biol.,1950
3. Ueber die Verwendung photographisch verkleinerten Optotypen zur Bestimmung der Sehschärfe in der Nähe;Bjerke;Arch. f. Ophth.,1902
4. 'acuité visuelle a la courte distance;Landolt;Arch. ophtal.,1916
5. Concerning observation of the sharpness of vision of abnormal eyes when tested at a distance and at near points;Snell;Tr. Am. Acad. Ophth.,1927