The term "REF" is an acronym that stands for "Referencing Electronic Journals". It refers to a method used by libraries and institutions to provide access to electronic journals, books or other resources. This involves creating unique identifiers (such as Digital Object Identifiers - DOIs) for each item, which are then referenced in the library's catalogue or database. When a user clicks on the reference link, they can access the full text of the resource through their institution's subscription.