·        NDLI (National Digital Library of India) https://ndl.iitkgp.ac.in/

·        DOAB (Directory of Open Access Books) https://www.doabooks.org/

·        DOAJ (Directory of Open Access Journals) https://doaj.org/

·        Open Access Theses and Dissertations https://oatd.org/

·        E-Books Directory  https://www.e-booksdirectory.com/

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