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https://www.washingtonpost.com/politics/gun-control-legislation-the-difference-between-1994-and-today/2012/12/17/b73d6212-487e-11e2-b6f0-e851e741d196_story.html?utm_term=.a18d808d522f
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http://www.texasgunlaws.org/
http://www.bbc.com/news/magazine-38365729