https://vocabularyserver.com/udc/en/ Universal Decimal Classification UDC Consortium UDC Consortium 2019-03-06 en 2019-03-06 15:43:30 Supreme authority. Sovereignty. Forms of state. Forms of government 2019-03-06 15:43:30https://vocabularyserver.com/udc/en/xml.php?skosTema=1051