American Psychological Association Zero Tolerance Task Force. (2008). Are zero tolerance policies effective in the schools? An evidentiary review and recommendations. American Psychologist, 63, 852 -- 862.
Centre for Disease Control and Prevention. (2010) Fact Sheet. Understanding School Violence, National Center for Injury Prevention and Control.
Dinkes, C. And Kelly, W. (2007). Indicators of school crime and safety: Washington, DC: National Center for Education Statistics, Institute of Education Sciences, U.S. Department of Education, and Bureau of Justice Statistics, Office of Justice Programs, U.S. Department of Justice.
Federal Bureau of Investigation. (1994 -- 2000). Uniform crime reports: Crime in the United States. Washington, DC: U.S. Government Printing Office