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Gargouri, Yassine, Hajjem, Chawki, Lariviere, Vincent, Gingras, Yves, Brody, Tim, Carr, Les and Harnad, Stevan (2010) Self-selected or mandated, open access increases citation impact for higher quality research. PLoS ONE, 5, (10), e13636-[5pp]. (doi:10.1371/journal.pone.0013636).