Issues in historical geography

The most significant advantage offered by hypermedia is the possibility of implementing a large variety of cognitive paths, using links to represent both extensional and intensional associative aspects. Authority files and thesauri can act as the most appropriate tools to build the cognitive layer of hypermedia, playing a twofold role: to formulate the query using a normalised language and to exploitthe power ofthe cognitive layer as a large set of semantically rich links the user will activate according to hislher specific interests. In this paper, we present the use of an authority file on authors and the ICONCLASS c!assification system to implement the cognitive layer of hypermedia and enhance user's search and navigation capabilities.