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2. Firearm availability and homicide rates across 26 high-income countries;Hemenway;J Trauma,2000
3. Uniform Crime Reports (UCR). Federal Bureau of Investigation, 2013. www.fbi.gov/about-us/cjis/ucr.
4. Targeting Guns: Firearms and Their Control;Kleck,1997
5. Rates of household firearm ownership and homicide across U.S. regions and states, 1988–1997;Miller;Am J Public Health,2002