_:b21564	<http://www.w3.org/2006/http#fieldValue>	_:b21578 .
_:b21564	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2006/http#MessageHeader> .
_:b21578	<http://www.w3.org/2006/http#elementName>	"OpenLink Virtuoso RDF crawler" .
_:b21564	<http://www.w3.org/2006/http#fieldName>	<http://www.w3.org/2006/http-header#user-agent> .
_:b21578	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2006/http#HeaderElement> .