1United Nations. International Plan of Action on Aging [EB/OL]. www. tin. org/esa/socdev/ageing/ageipaal, htm, 2003.
2United Nations. Human Development Report [R]. New York.. United Nations Development Programme, 2005.
3United Nations. World Population Ageing: 1950-2050 [ EB/OL]. www. un. org/esa/population/publications/ worldageing19502050/index, htm, 2002.
4United Nations Population Division. World Population Prospects: The 2010 Revision [M]. New York: UN Popula- tion Division, 2011.
5David E. Bloom, Axel Boersch-Supan, Patrick McGee, Atsushi Seike. Population Aging: Facts, Challenges, and Re- sponses [Z]. Harvard PGDA Working Paper No. 71, 2011.
7OECD. Increases in Pension Contributions in the OECD Countries between 1994 and 2004 Were not Significant [Z]. Paris: Organisation for Economic Co-operation and Development, 2007.
8Economic Policy Committee (EPC). Budgetary Challenges Posed by Ageing Populations: The Impact on Public Spending on Pensions, Health and Long-term Care for the Elderly and Possible Indicators of the Long-term Sustain- ability of Public Finances [Z]. Brussels: European Union, 2001.
9Eurostat. Expenditure on Pensions [J/OL]. www. europa, eu, 2007.
10J. Myles, P. Pierson. The Comparative Political Economy of Pension Reform [M]. The New Politics of the Welfare State, Oxford University Press, 2001.