About: http://webisa.webdatacommons.org/276003745

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 only thing I used about balls is that the Minkowski sum of a ball and a ball is a ball of the correct size.
http://www.w3.org/ns/prov#wasQuotedFrom	mathoverflow.net