Open Educational Resources or OER can be defined as:
"Teaching, learning, and research materials that reside in the public domain or have been released under an open license that permits their free use and adaptation by others" (Creative Commons).
Kansas Libretext Commons
Kansas Board of Regents OER Taskforce has a Libretext page for OER authored in Kansas
Digital Commons Network
"The Digital Commons Network brings together free, full-text scholarly articles from hundreds of universities and colleges worldwide."