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Free access to knowledge is a central module within the context of Science 2.0. Rapid development within the area of Open Access underlines this fact and is a pathfinder for Science 2.0, especially since the October 2003 enactment of the ‘‘Berlin Declaration on Open Access to Knowledge in the Sci- ences and Humanities’’. Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities (http://oa.mpg.de/files/2010/04/berlin_declaration.pdf).
Sitek, D., & Bertelmann, R. (2014). Open Access: A State of the Art. In Opening Science (pp. 139–153). Springer International Publishing. https://doi.org/10.1007/978-3-319-00026-8_9