1. Institute of Medicine Report. http://www.iom.edu
2. Sleep complaints among elderly persons;Foley;An epidemiologic study of three communities,1995
3. National Sleep Foundation. http://www.sleepfoundation.org
4. Correlates of sleep complaints in adults;Phillips;The ARIC Study,2005
5. How age and daytime activities are related to insomnia in the general population;Ohayon;Consequences for older people,2001