Prions by BioWiki, University of California, Davis.
Links for What are Prions?:
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  http://biowiki.ucdavis.edu/Microbiology/Prions
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  Prion Basics by the Department of Microbiology Immunology & Pathology, College of Veterinary Medicine & Biomedical Sciences 
 Colorado State University, Fort Collins, Colorado, U.S.A..http://csu-cvmbs.colostate.edu/academics/mip/prion-research-center/Pages/Prion-Basics.aspx
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  What are prions? by the Prion Alliance, a non-profit devoted exclusively to advancing scientific research towards a treatment or cure for human prion disease. http://www.prionalliance.org/2013/11/26/what-are-prions/
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  Prions by Wikipedia, the free encyclopedia. https://en.wikipedia.org/wiki/Prion


