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Universal Decimal Classification Summary
UDC Summary


The Multilingual Universal Decimal Classification Summary - UDC Summary (udcS) for short - represents a selection of around 2,600 classes extracted from the UDC Master Reference File (UDC MRF) 2011 which contains over 70,000 classes. The selection comprises main numbers, common auxiliary numbers and special auxiliary numbers and it represents even coverage of all areas of knowledge as contained by the scheme. UDC is updated annually and UDC Summary represents always the latest version of UDC.

The UDC Summary is held in a multilingual database that mirrors the structure of the UDC MRF database and in that respect represents the full set of data and can be used as a UDC demonstrator for training, research, various information organization and retrieval purposes.

The plan for the UDC Summary is that it includes translations to as many languages as possible and mappings to other knowledge organization systems and that this data is made available for free in various standard formats.

Since 2011 UDC Summary has been available as linked data (SKOS) from The enrichment of the original data set with languages and mappings depends on voluntary input from user communities world-wide.
This is the RDF Schema for the UDC Classification Scheme


UDC Consortium


UDC Summary is the intellectual property of the UDC Consortium and was first released by the UDC Consortium in October 2009 (last updated in August 2012) under the Creative Commons Attribution Share Alike 3.0 license. With this licence you may copy and reuse the UDC Summary on condition that you attribute the work to the UDC Consortium. Any redistribution should be under the same licence.


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