The Open Textbook Library (OTL) is managed by the Open Textbook Network at the University of Minnesota. Books published by many open publishers, such as OpenStax, BC Campus, Open SUNY, and more are aggregated in the OTL. Anyone can suggest a title be added to the library, but the book must meet these criteria.
OTL's FAQ: https://open.umn.edu/opentextbooks/faq
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