About: http://webisa.webdatacommons.org/260028561

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	(wherein, R represents a hydrogen atom or a methyl group, and R1 represents a lower alkyl group, so that the group represents the structural unit (a1) when R is a hydrogen atom, and the structural unit (a1???) when R is a methyl group)
http://www.w3.org/ns/prov#wasQuotedFrom	google.es