1. Associated Press, (2005) Number of centenarians in Japan reaches record 25,606, 13 September.
2. Campbell, J. C. (2003) Population Ageing: Hardly Japan's Biggest Problem, Asia Program Special Report No. 107, Woodrow Wilson International Centre for Scholars, January, pp. 10–15.
3. Japan's Radical Reform of Long-term Care
4. Committee for Social Development, (2001) International Strategy for Action on Ageing, United Nations.