1. The optimum quantity of debt;S Aiyagari;Journal of Monetary Economics,1998
2. Global demographic trends and social security reform;O Attanasio;Journal on Monetary Economics,2007
3. Demographics and the Political Sustainability of Pay-as-You-Go Social Security in Pension Strategies in Europe and in the United States;T Bergstrom;Massachusetts Institue of Technology,2008
4. Statutory pensions in Finland. Long-term projections 2007. Finnish Centre for Pensions;P Bistr�m;Reports,2008
5. Debt, deficit s and finate horizons;O Blanchard;Journl of Political Economy,1985