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The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
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The https:// ensures that you are connecting to the
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Webb SE, Needham SR, Roberts SK, Martin-Fernandez ML.Webb SE, et al.Opt Lett. 2006 Jul 15;31(14):2157-9. doi: 10.1364/ol.31.002157.Opt Lett. 2006.PMID: 16794711