So You Wanted to Know…How Does Full Text? SFX work?
How does clicking on this button next to the article you want to read take you to the full text of the article in just a few clicks of the mouse? The answer is with the help of OpenURL technology and a product called a Link Resolver.
A link resolver uses OpenURL technology to take users from an article citation within a database to the full text of the article. Each article citation found in databases such as Medline/PubMed or Scopus or Google Scholar contains descriptive information called metadata such as journal title, author, and page numbers. An OpenURL is a URL that contains this descriptive metadata. There are a variety of link resolver products available. Mayo Clinic Libraries uses SFX.
Within each link resolver is a knowledge base, which contains details about the library’s electronic journal holdings including starting date, ending date, or full text embargo information. Library staff maintains the knowledge base locally, and makes updates as electronic journal access changes. The knowledge base also contains electronic menu configuration files which determine what services will be offered to users and under what circumstances.
Essentially, the link resolver acts as an intermediary between a database or Source and the desired service, or Target. When a user clicks on the SFX button next to a citation the source database sends the OpenURL to the link resolver. The link resolver decodes the OpenURL, then based on the parameters defined in the knowledge base, generates a menu of service choices.
When full text is selected the link resolver sends the Open URL to the Target e-journal publisher. Link resolvers work in conjunction with CrossRef, which is the official DOI (Digital Object Identifier) registry for scholarly publications. A DOI is a unique alphanumeric string assigned to a digital object, usually a journal article or book chapter. Some publishers require link resolvers to use a DOI for article level linking, however the DOI is not always available in the OpenURL received from the source database. The link resolver is able to query the CrossRef database when needed in order to obtain the DOI to facilitate linking directly to the article from the SFX menu.
Submitted by Kelly A. Arp
Acquisitions & Electronic Resources Librarian
Entry filed under: Feature Articles.