April 20, 1999 – The Columbine High School Shootings

Columbine High School Massacre – Wikipedia
Columbine High School – CHS Website
Columbine Memorial – Columbine Memorial.org
Columbine Pages – Jefferson County Sheriff (CNN)
Columbine High School Shootings – Rocky Mountain News
4-20: a Columbine Site – A Columbine Site.com
Audio – Video Archive – A Columbine Site.com
Columbine: Massacre and Aftermath – Life
Columbine, Ten Years On – The First Post
The Depressive and the Psychopath – Slate
Debunking the Myths of Columbine, 10 years Later – CNN
10 Years Later, the real story behind Columbine – USA Today