Heller, P. S. (2003). Who will pay?: Coping with aging societies, climate change, and other long-term fiscal challenges. International Monetary Fund.
Chicago-viite (17. p.)Heller, Peter S. Who Will Pay?: Coping with Aging Societies, Climate Change, and Other Long-term Fiscal Challenges. Washington, D. C: International Monetary Fund, 2003.
MLA-viite (9. p.)Heller, Peter S. Who Will Pay?: Coping with Aging Societies, Climate Change, and Other Long-term Fiscal Challenges. International Monetary Fund, 2003.
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