An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Calasso M, Parmeggiani PL.Calasso M, et al. Among authors: parmeggiani pl.Sleep. 2008 May;31(5):701-7. doi: 10.1093/sleep/31.5.701.Sleep. 2008.PMID: 18517039Free PMC article.