Recommended Amount of Sleep for a Healthy Adult:  A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society

Read whichever section(s) that is of interest to you (for those interested in depth). (120 minutes)

National Center for Biotechnology Information,  U.S. National Library of Medicine, National Institutes of Health - 2006

Click http://www.ncbi.nlm.nih.gov/books/NBK19960/ link to open resource.