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PrefixNamespace IRI
isaphttp://webisa.webdatacommons.org/prov/
isahttp://webisa.webdatacommons.org/
rdfhttp://www.w3.org/1999/02/22-rdf-syntax-ns#
provhttp://www.w3.org/ns/prov#
xsdhhttp://www.w3.org/2001/XMLSchema#
n4joomla.
Subject Item
isa:116974817
rdf:type
prov:Entity
prov:value
I have exactly the same error.Deleted all directories except templates and images and installed 1.5.21 changing to existing database afterwards.
prov:wasQuotedFrom
n4:org
Subject Item
isap:339030704
prov:wasDerivedFrom
isa:116974817
Subject Item
isap:182852678
prov:wasDerivedFrom
isa:116974817