1. Steg, H., Strese, H., Hull, J., Schmidt, S.: Europe is facing a demographic challenge Ambient Assisted Living offers solutions (2005)
2. International Organization for Standardization. DIN EN ISO 13407
3. http://www.instantreality.org
4. W3C World Wide Web Consortium,
http://www.w3.org/TR/owl-guide/
5. Cumming, E., Henry, W.: Growing old: the process of disengagement. Basic Books, New York (1961)