About: http://webisa.webdatacommons.org/345829058

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	It is even more preferred that R2 and R3 are the same and contain 1 or 2 carbon atoms and most especially 2 carbon atoms.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com