About: http://webisa.webdatacommons.org/175366990

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Like /etc/passwd the x just denotes that there is an existing entry in the shadow-file (which in turn contains the hashed password. gconv will create a missing gshadow-entry and create that x.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com