This file was published in a Public Library of Science journal. Their websitestates that the content of all PLOS journals is published under the Creative Commons Attribution 3.0 license, unless indicated otherwise. Previously, PLOS used the Creative Commons Attribution 2.5 license.
This file contains additional information, such as EXIF metadata, probably added from the digital camera or scanner used to create or digitize it.
If the file has been modified from its original state, some details may not fully reflect the modified file. The timestamp is only as accurate as the clock in the camera and may be completely wrong.