SRU interface to the CERL Thesaurus

CERL members and other interested institutions may make use of the CERL Thesaurus in their own database environment as

For this purposes the CERL Thesaurus can be accessed by a remote software application (e.g. a database system) via the Search and Retrieve URL (SRU) protocol. SRU is a newly emerging protocol for querying remote databases. It might be understood as a descendant of the widely used Z39.50 protocol, but based on XML and HTTP and thus remarkably reducing the complexity of Z39.50.

Technical Details

The CERL Thesaurus SRU interface currently supports the protocol version 1.1 and is available from Please see the Explain record for details on the available indexes.

Records are available in MARCXML 1) and a specific output format for implementations of Assisted Searching. A description of the record structure is available from this document: CTAS Format Description v1.1 - changes to the former CTAS version (CTAS Format Description v1.0) are marked in red.

Further Reading

Please note: The XML encoding follows the MARCXML schema, but the fields used are not MARC21 but those of the CERL Thesaurus' internal format