1. Testing of visual acuity in preschoolchildren. Norms, variables and a new picture test;Allen;Pediatrics,1957
2. Preschool vision screening;Cunningham;Amer. J. publ. Hlth.,1959
3. Amblyopia ex anopsia: A preventable form of blindness;Gundersen;Ped. Clin. North America.,1955
4. The examination of the visual acuity of children;Jonkers;Ophthalmologica (Basel),1958
5. Vergleichende Untersuchungen an Sehproben für die Fernvisusbestimmung;Monjé;Klin. Mbl. Augenheilk.,1950