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Brain, Marshall. "How Sleep Works." 01 April 2000. HowStuffWorks.com. <http://health.howstuffworks.com/sleep.htm> 09 May 2008.
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Please copy/paste the following text to properly cite this How Stuff Works article:
Brain, Marshall. "How Sleep Works." 01 April 2000. HowStuffWorks.com. <http://health.howstuffworks.com/sleep.htm> 09 May 2008.
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