1. On emmetropia and ametropia;van Alpen;Ophthalmologica (Suppl.),1961
2. Infant refraction and accommodation;Banks,1980
3. Clinical refraction;Borish,1970
4. Accommodation and refraction of the eye;Donders,1952
5. An investigation of the effect on the eyes of occupations involving close work;Duke-Elder;British Journal of Ophthalmology,1930