Connexions/Open Stax is a repository of over 17,000 learning objects or modules and over 1000 textbooks and journal articles provided and maintained by Rice University. All content is licensed under a Creative Commons license that allows for reuse and remixing materials, provided the original source author is cited.
The Open Textbook Library is a collection of over 300 freely available electronic textbooks licensed under one of six Creative Commons licenses. Some books include faculty peer reviews. All can be read online or are downloadable for offline reading.
Milne Library Publishing at SUNY Geneseo manages and maintains Milne Open Textbooks, a catalog of open textbooks authored and peer-reviewed by SUNY faculty and staff..
HathiTrust is a shared digital repository created by major research libraries. It offers searching of the full text of books and full access to works in the public domain.
MERLOT is a collection of peer-reviewed higher education, online learning materials. Materials are cataloged by registered members, and cover a variety of subjects.
OAPEN (Open Access Publishing in European Networks) provides freely accessible academic books, mainly in humanities and social sciences. The publishers included in OAPEN are screened for quality and peer review processes.
Project Gutenberg offers over 70,000 free ebooks available in the public domain to download to your PC, Kindle, Android, iOS or other portable device. Choose between ePub, Kindle, HTML and simple text formats.
