1. Andreasen, N. C. (1985). Post-traumatic stress disorder. In H. I. Kaplan & B. J. Sadock (Eds.), The comprehensive textbook of psychiatry (pp. 918–924). Baltimore, MD: Johns Hopkins University Press.
2. Becker, E. (1973). The denial of death. New York, NY: Free Press.
3. Berkvist, R. (2008, April 6). Charlton Heston, Epic Film Star and Voice of N.R.A., Dies at 84. New York Times.
4. Boggioni, T. (2014, May 12). Sandy Hook truther steals memorial sign, tells victim’s mother her child never existed, Raw Story. Retrieved from http://www.rawstory.com/rs/2014/05/12/sandy-hook-truther-steals-memorial-sign-tells-victims-mother-her-child-never-existed/
5. Cohen A. P., Azrael, D., & Miller, M. (2014, October 15). Rate of mass shootings has tripled since 2011, Harvard Research Shows. Mother Jones.