1. 1. U.S. Census Bureau: Income 2001. Available at: http://www.census.gov/hhes/income. Accessed July 15, 2003.
2. 2. Federal Agency for Civic Education. Available at: http://www.bpb.de/die-bpb/138852/federal-agency-for-civic-education. Accessed January 12, 2017.
3. 3. The Human Mortality Database: Germany, Total population. Available at: http://www.mortality.org/cgi-bin/hmd/country.php?cntr=DEU&level=2. Accessed January 12, 2017.
4. 4. European Heart Network: European Cardiovascular Disease Statistics 2012. Available at: http://www.ehnheart.org/cvd-statistics.html. Accessed January 12, 2017.
5. 5. Schwartz JB, Zipes DP. Cardiovascular disease in the elderly. In: Bonow RO, Mann DL, Zipes DP, Libby P, Braunwald E, eds. Braunwald’s Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, PA: Elsevier Saunders; 2012: 1727-56.