1. ABCNEWS.com. (2002, January 28). Suffering from sleep debt? The dangers of chronic sleep deprivation.Retrieved July 28, 2002 from http://abcnews.go.com/sections/community/2020/chat_sleepdeprivation0404.html
2. American Sleep Disorders Association. Diagnostic Classification Steering Committee. (1990). The international classification of sleep disorders: Diagnostic and coding manual. Rochester, MN: Author.
3. Personality differences between short and long sleepers
4. Coren, S. (1996). Sleep thieves. New York: Simon & Schuster.