About: http://webisa.webdatacommons.org/114199673

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	Most of these have been prepared from coal tar or petroleum, being formed from an aromatic hydrocarbon such as benzene, from which indigo is derived (see also aniline), or anthracene, which yields alizarin.
http://www.w3.org/ns/prov#wasQuotedFrom	questia.com