1. Studienüber die Accomodation des Vogelauges;Beer;Archiev Gesamte Physiolgie,1893
2. Het Accommodatievermogen der Oogen, physiologisch toegelicht;Cramer,1853
3. The vision of vertebrates;Duke-Elder,1958
4. Control of choroidal blood flow by the nucleus of Edinger-Westphal in pigeons: A laser doppler study;Fitzgerald;Investigative Ophthalmology and Visual Science,1990
5. Lenticular accommodation in chicks is mediated primarily by a contraction of the iris sphincter muscle;Glasser;Society of Neuroscience Abstracts,1993