3McEntyre JR, Ananiadou S, Andrews S, et al. UKPMC: a full textarticle resource for the life sciences[J]. Nucleic acidsresearch,2011,39(Database issue):D58-D65.
4Roberts RJ. PubMed Central: The GenBank of the publishedliterature[J]. Proceedings of the National Academy of Scienceof USA,2001,98(2):381-382.
5The Omnibus Appropriations Act of 2009 Makes the NIH PublicAccess Policy Permanent[EB/OL].[2014-08-20].http://grants.nih.gov/grants/guide/notice-files/NOT-OD-09-071.html.
