About: http://webisa.webdatacommons.org/210699447

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	For those applications where the static height differential is more than a few inches or the fluid flow dependent pressure drop is more than a few tenths of a psi, however, some sort of external pumping is necessary.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com