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2. Global Status Report on Noncommunicable Diseases 2014,2014
3. Eurostat—Data Explorerhttp://appsso.eurostat.ec.europa.eu/nui/submitViewTableAction.do
4. Trends in Permanent Pacemaker Implantation in the United States From 1993 to 2009
5. ResponseCare—Technical Services, Medtronic©http://www.responsecare.medtronic.com/technical-services/index.htm