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.
Gañán-Calvo AM, Gordillo JM.Gañán-Calvo AM, et al.Phys Rev Lett. 2001 Dec 31;87(27 Pt 1):274501. doi: 10.1103/PhysRevLett.87.274501. Epub 2001 Dec 11.Phys Rev Lett. 2001.PMID: 11800883
Gañán-Calvo AM.Gañán-Calvo AM.Phys Rev Lett. 2007 Mar 30;98(13):134503. doi: 10.1103/PhysRevLett.98.134503. Epub 2007 Mar 30.Phys Rev Lett. 2007.PMID: 17501206