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.
Sontag RL, Weber TJ.Sontag RL, et al. Among authors: weber tj.BMC Res Notes. 2012 May 4;5:217. doi: 10.1186/1756-0500-5-217.BMC Res Notes. 2012.PMID: 22559742Free PMC article.