“Solving the Gun Control Issue in the United States: A Comprehensive Approach”

I am a little short on time to accurately do this. 
My professor is asking for a research paper on gun control in the US. She instructed it should either take a stance or write about solving the issue. 
I want my paper to be about solving the problem of gun control. 
A total of 4 sources must be used with one coming from this article  – Research Funding | Everytown Research & Policy. 
please try to find up-to-date sources that i can add on my work cited page