About: http://webisa.webdatacommons.org/14097043

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	The letter of introduction, along with the visiting card, was an important part of polite social interaction in the 18th and 19th centuries.
http://www.w3.org/ns/prov#wasQuotedFrom	wikipedia.org