National Institute of Health Public Access: In order to insure public access to all articles arising from NIH funds, the National Institute of Health requires mandatory submission of manuscripts to PMC (formerly PubMed Central).
http://publicaccess.nih.gov/index.htm |

BioMed Central is a publisher of research
articles in Science, Technology and Medicine. Articles can be freely accessed, re-used and re-distributed.
http://www.biomedcentral.com/
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Public Library of Science: PLoS is a nonprofit organization of scientists and physicians committed to making the world's scientific and medical literature a freely available public resource.
http://www.plos.org/
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PMC (formerly PubMed Central) is the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature.
http://www.ncbi.nlm.nih.gov/pmc/
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