About: http://webisa.webdatacommons.org/185314547

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	those of the lanthanide and actinide series of the Periodic Table, and n is an integer equal to the valence of M. Such preferred sulfonic acid catalysts and derivatives thereof are more fully described in U.S. Pat. No. 3,842,019.
http://www.w3.org/ns/prov#wasQuotedFrom	google.ca