A repository is a collection of other smaller OA sites and collections. Repositories are useful for searching for other OA collections.
These are collections of OA journals. You can search by title and content keywords.
Academic institutional repositories have off open access to scholarship often through preprints. Most institutions of higher education have an institutional scholarly repository. You can search by institution name and "OA" or "repository" They are often housed through the institution's library. Here are a few examples:
Authors often retain the right to their scholarship and make them available on scholarly sites.
Subject repositories are open to scholars all over the world who publish work in a particular discipline. Some of the larger ones include:
Adapted from https://osc.universityofcalifornia.edu/for-authors/open-access/#green
A searchable and browsable database of open access books.
Free online access to monographs in different Humanities and Social Sciences disciplines.
A video that provides an overview of OAPEN's (Open Access Publishing in European Networks) study and recommendations of open access monograph publishing.
A list of business models and revenue sources for open access book publishing
Searches for master's theses and PhD dissertations published around the world.
Multidisciplinary repository of theses and dissertations.
OA theses and dissertations through Ebsco