Preker, A. S., Scheffler, R. M., & Bassett, M. C. (2007). Private voluntary health insurance in development: Friend or foe. World Bank.
Chicago-viite (17. p.)Preker, Alexander S., Richard M. Scheffler, ja Mark C. Bassett. Private Voluntary Health Insurance in Development: Friend or Foe. Washington, D.C.: World Bank, 2007.
MLA-viite (9. p.)Preker, Alexander S., et al. Private Voluntary Health Insurance in Development: Friend or Foe. World Bank, 2007.
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