Z39.50 is a client/server protocol widely used in digital libraries and mauseums for searching and retrieving information spreal over a unmber of heterogenous sources. To overcome semantic and schematic discrepancies among the various data sources the protocol relies on a world view of information as a flat list of fields, called Access Points (AP). One of the major issues for building Z39.50 wrappers is to map this unstructured list of APs to the underlying soruce data. Unfortunately, existing Z39.50 wrappers have been developed from scratch and they do not provide high-level mapping languages with verifiable properties.
展开▼
