1. Vision Impairment and Blindness
https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-impairment
2. US Patent Application for Refreshable Braille Display Patent Application (Application #20130203022 issued 8 August 2013)—Justia Patents Search
https://patents.justia.com/patent/20130203022
3. Screen Reader/2—Programmed access to the GUI;Thatcher,1994
4. IBM SCREEN READER/2
www-01.ibm.com/common/ssi/cgi-bin/ssialias