SURF has developed a database with metadata of and references to documents at the request of MBO institutions, universities of applied sciences and universities. Institutions link systems to this database that contain previously submitted work, such as document repositories and ELEs. Institutions can then populate the database, choosing which documents to add. In principle, there will only be metadata of the documents and a link to the document itself with the key. If desired, a copy of the document itself can also be stored (if it needs to be made available for longer than it is stored in the source). The supplier of plagiarism scanning software also connects to the database