1. The sensitive period;Von Noorden;Trans Ophthalmol Soc UK,1979
2. Report of the Children's Sub-group of the National Screening Committee,2000
3. Snowdon SH, Stewart-Brown SL. Preschool vision screening: results of a systematic review. CRD Report 9. York: NHS Centre for Reviews & Dissemination.
4. Amblyopia: is visual loss permanent?;El Mallah;Br J Ophthalmol,2000
5. Bielschowsky A. Ueber monoculäre Diplopie ohne physikalische Grundlage nebst Bemerkungen über da Sehen Schielender. Cited in reference 1 above.