1. Directory of Open Access Books (DOAB)
   
   The Directory of Open Access Books (DOAB) is a discovery service for peer reviewed books published under an open access license. DOAB provides a searchable index to the information about these books, with links to the full texts of the publications at the publisher’s website or repository.
2. Directory of Open Access Journals (DOAJ)
   The Directory of Open Access Journals (DOAJ) lists free, full text, quality controlled scientific and scholarly journals, covering all subjects and languages.
3. OpenDOAR

OpenDOAR is an authoritative directory of academic open access repositories. Contain digital collections that preserve and provide access of intellectual output of an institution.As well as providing a simple repository list, OpenDOAR lets you search for repositories or search repository contents

4. Bioline International

Bioline International It provides open access to peer reviewed bioscience journals published in developing countries. The journals contain timely research on public health, international development, tropical medicine, food and nutritional security, and biodiversity

5. Highwire Press

HighWire Press is a division of the Stanford University Libraries that produces the online versions of peer-reviewed journals and other scholarly content. Resources include a vast database of full-text scholarly, high-impact materials.

6. Makerere Institutional Repository (Mak IR)

Mak IR is a collection of scholarly output of by researchers of Makerere University, including scholarly articles and books, electronic theses and dissertations, conference proceedings, technical reports and digitized library collections. It is the official Institutional Repository (IR) of Makerere University.

7. Virginia Tech University

Provides access to theses and dissertations generated by a variety of harvesters and search engines in cooperation with the NDLTD–Networked Digital Library of Theses and Dissertations.

8. Ethos: Electronic Theses Online Service

Requires one to register. Provides access to over 350,000 UK doctoral theses

9. Subject Repositories

Institutional repositories: “digital collections that preserve and provide access the intellectual output of a Subject area, Contents vary. Full text or bibliographic. Most of them are open access, examples,

10. Arxiv
    
    Provides open access to 855,382 e-prints in Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance and Statistics. Contains open e-print archive with over 100000 articles in physics, 10000 in mathematics, and 1000 in computer science.
11. Social Science Research Network (SSRN)
    
    Social Science Research Network (SSRN) is devoted to the rapid worldwide dissemination of social science research and is composed of a number of specialized research networks in each of the social sciences.
12. org
    
    WorldWideScience.org: provides one-stop searching of national and international scientific databases and portals.
13. Open Access Educational Resources/Courseware

Provide open access learning objects: Quiz, Syllabi, course outline, notes, presentations, simulations, games, videos, podcasts etc. Mostly feature a community of users. Among others, these include:

14. Merlot
    
    MERLOT is a free and open online community of resources designed primarily for faculty, staff and students of higher education from around the world to share their learning materials and pedagogy.   MERLOT is a leading edge, user-centered, collection of peer reviewed higher education, online learning materials, catalogued by registered members and a set of faculty development support services.
15. Open Educational Resources (OER)

Open Educational Resources (OER) are teaching and learning materials that you may freely use and reuse, without charge for teachers and learner Worldwide learning network of shared teaching and learning materials made freely available online. Grouped by subject area and grade

16. Tufts Open Courseware

Is a free and open educational resource for faculty, students, and self-learners around the world Public Domain Resources

17. Project Gutenberg
    
    Allows free download eBooks from kindle, android, ipad, nook, epub or read online.
18. Internet Archive
    Provides free access to researchers, historians, scholars, the print disabled, and the general public.
19. HeinOnline International Core opens research to a new level with an entire digital library of authoritative sources that both illuminate the past and inform on the present
20. Alberta Law Review
21. Amsterdam Law reform
22. Goettingen Journal of International Law
23. Journal of Law and Commerce
24. AnnalesGeophysicae
25. Earth Planets and Space
26. British Medical Journal (BMJ):
27. Biomed central:
28. Free Medical Journals:
29. Public Library of Science:
30. Springer Open Journals