1. https://www.washingtonpost.com/national/history-of-gun- control-legislation/2012/12/22/80c8d624-4ad3-11e2-9a42- d1ce6d0ed278_story.html?utm_term=.d3f2077ebab4
2. http://www.washingtonexaminer.com/its-still-legal-to-own-a- machine-gun-its-also-extremely-difficult-and-especially-expensive/ article/2636302
3. http://www.motherjones.com/politics/2012/12/mass-shootings-mother-jones-full-data/
4. https://www.nytimes.com/interactive/2017/06/05/upshot/opioid- epidemic-drug-overdose-deaths-are-rising-faster-than-ever.html
5. https://www.vox.com/cards/war-on-drugs-marijuana-cocaine- heroin-meth/war-on-drugs-cost-spending
6. http://news.gallup.com/poll/165605/personal-safety-top-reason- americans-own-guns-today.aspx