About: http://webisa.webdatacommons.org/394279580

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	In particular, are there situations in which it can return NULL or some other invalid string? (string is not a standard C type, but I guess that string is an alias for char*, otherwise the call to strlen would not compile).
http://www.w3.org/ns/prov#wasQuotedFrom	stackoverflow.com