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More than 400 mio. scientific documents from more than 11.000 content providers. BASE is one of the world's most voluminous search engines for academic web resources.

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Open Access Library (www.oalib.com) is an academic search engine and publisher. You can download research papers for free and submit your paper to it. It is a shared academic database.

DOAJ is a unique and extensive index of diverse open access journals from around the world, driven by a growing community, committed to ensuring quality content is freely available online for everyone.