Maberley DA, Hollands H, Chuo J, Tam G, Konkal J, Roesch M, ve diğerleri. (March 2006). "The prevalence of low vision and blindness in Canada". Eye. 20 (3): 341-6. doi:10.1038/sj.eye.6701879. PMID15905873.
Maberley DA, Hollands H, Chuo J, Tam G, Konkal J, Roesch M, ve diğerleri. (March 2006). "The prevalence of low vision and blindness in Canada". Eye. 20 (3): 341-6. doi:10.1038/sj.eye.6701879. PMID15905873.