American Institute of Mathematics approved open textbooks
2012 Book Archive Creative Commons-licensed copies of all the books which were available online from a specific publisher at the end of 2012.
Bookboon Online textbooks for free
Digital Collections Library of the Congress
DOAB This directory is open to all publishers who publish academic, peer reviewed books in Open Access
FlatWorld digital textbooks
Harvard Law School Free Legal Research Resources - Foreign and International
Highly Rated Textbooks by Cool4Ed
INTECH Science, Technology & Medicine Open Access books
International Children's Digital Library
Knowledge Unlatched Their ambition is to include all Open Access book content worldwide on one platform for user-friendly discovery
Libretexts Multi-institutional collaborative effort to improve education at all levels of higher learning by developing Open Access Resources
Loyal Books Free Public Domain Audiobooks and eBooks Downloads
Lumen Learning Covering 50+ high-enrollment college subjects
Manybooks all types of free and low cost reading books
MUSE in collaboration with Cornell University Press
OAPEN freely accessible academic books, mainly in the area of humanities and social sciences
Open Access Texts Open textbooks for open education
Openhumanitiespress International, scholar-led open access publishing collective
Open Research Library promotes Open Access to scholarly works
Open SUNY Textbooks State University of New York
Open Culture Stanford University
Open Textbook Library University of Minnesota
OAPEN freely accessible academic books, mainly in the area of humanities and social sciences
Pressbooks Directory This directory provides an index of thousands of books
Project Gutenberg mostly public domain books
SmallBeerPress Creative Commons Licensed Works
Textbook Revolution a student-run site dedicated to increasing the use of free educational materials by teachers and professors
The Public Domain Review focus on works which have now fallen into the public domain
Home Page • OER and AL$ Basic Resources • Open Textbook Repositories • Open Access Journals • Open Course Repositories • Subject Specialized Sites • Simulations • Free Audiovisual Resources • Free OER Creation Tools • Open Source eBook Creation • Creative Commons Licensing • OER Search Engines • OER Games • OER Self Publishing • OER Funding Opportunities • Articles and Research on OER • OER Evaluation Rubrics • CSUF Subscriptions and Free-to-user Apps • Open Textbooks by CSU Faculty Members
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