1. Annual Report on the Aging Society: 2010, Cabinet Office Japan,
http://www8.cao.go.jp/kourei/english/annualreport/2010/pdf/p2-3.pdf
2. Association of Cochlear Implant Transmitted Audition (ACITA),
http://www2u.biglobe.ne.jp/~momo1/sub1/new_sub/akemi100619.html
3. Ayako, F., Hiroaki, N., Takehiko, Y.: Speech Balloon Captioning System for Meetings based on Automatic Speech Recognition. In: Proc. 13th International Conference on Human-Computer Interaction (HCII 2009), pp. 313–317 (2009)
4. BBC,
http://www.bbc.co.uk/news/technology-14654339
5. Mizuno, E.: Investigation of Hearing Compensation Needs and Issues in Elderly People. LifeDesign REPORT (January-February 2009)