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. 2015 Mar 17;3:e829. doi: 10.7717/peerj.829

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© 2015 Casey et al.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited.

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(A) Number of open access versus pay-per-view publications. (B) Number of cumulative citations by open versus non-open access publications. (C) Average number of citations per open and pay-per-view publication.