This solution may create copyright problems, which must be considered. At least we hope this can be used for older material. The metadata records are stored in the holdings database or in other databases, with links to the electronic document. When doing a web search, such documents can be presented on the screen. Today we do not have the final system to take care of such documents, as they have to be stored in the file system.
Many periodicals are now available in an electronic format.
It is possible to search by title, get a list of electronic periodicals subscribed to at a given library, and get an electronic presentation of these periodicals. This database has been created on the basis of information given by the vendors. Here they will have to use the vendors' own interface. International projects have for many years worked on integrating different library databases. A search protocol, Z39.50, has been developed making this possible.