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.
Siebeling L, ter Riet G, van der Wal WM, Geskus RB, Zoller M, Muggensturm P, Joleska I, Puhan MA.Siebeling L, et al. Among authors: puhan ma.BMC Pulm Med. 2009 May 6;9:15. doi: 10.1186/1471-2466-9-15.BMC Pulm Med. 2009.PMID: 19419546Free PMC article.