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.
Bainbridge ET, Matthews HR.Bainbridge ET, et al. Among authors: matthews hr.Thorax. 1980 Apr;35(4):264-8. doi: 10.1136/thx.35.4.264.Thorax. 1980.PMID: 7434267Free PMC article.
Moran A, Stableforth DE, Matthews HR.Moran A, et al. Among authors: matthews hr.Thorax. 1989 Dec;44(12):1051-2. doi: 10.1136/thx.44.12.1051.Thorax. 1989.PMID: 2617445Free PMC article.