About: http://webisa.webdatacommons.org/232509554

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	As mentioned above, prior art pneumatic devices have been used to propel balls with a desired trajectory and velocity for practice activities relating to such sports as baseball and tennis.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com