Open Access repositories store copies of scholarly and research materials that are available for public use. They are usually maintained by academic institutions, libraries, publishers, or organizations. Some of these repositories post papers before or after their publication in scholarly journals, and different versions of papers may appear. Repositories may contain text, data, presentations, and multimedia materials.

Examples: Scholars Archive,  arXiv.org,  RePEc: Research Papers in Economics
 
To evaluate the content in an open access repository, look for these clues:

• The repository is sponsored by a reputable academic institution, library, publisher, or organization.


• The repository is searchable in OAISTER, a reputable union catalog of academic‐oriented digital resources.


• The author has expertise on the topic. This will apply to more recent, as opposed to historical, documents.


• If the document in question is an article, it has been published in a reputable journal. The identity of the “official” publication in a journal can help determine the copy of record for the publication.


• The material you are interested in cites sources that you can use to verify the information.