1. World Health Organization. (2014). "Visual impairment and blindness". Fact Sheet n°282. Retrieved from: http://www.who.int/mediacentre/factsheets/fs282/en/ Accessed on: January 16th 2016. World Health Organization. (2014). "Visual impairment and blindness". Fact Sheet n°282. Retrieved from: http://www.who.int/mediacentre/factsheets/fs282/en/ Accessed on: January 16th 2016.
2. World Health Organization. (2010). "International Statistical Classification of Diseases and Related Health Problems" (ICD-10 -Vol. 2). World Health Organization. (2010). "International Statistical Classification of Diseases and Related Health Problems" (ICD-10 -Vol. 2).
3. Providing accessibility to blind people using GIS