SHERPA RoMEO is an online resource which aggregates and analyses publisher open access policies from around the world and provides summaries of self-archiving permissions and conditions of rights given to authors on a journal-by-journal basis. Repository managers and authors can use this service to find out which version of their articles can be self-archived under what condition.
University of Southampton Library provides a comprehensive guide for the definitions of article versions to be uploaded in a repository as well as explaining Creative Commons license open licences.