<http://webisa.webdatacommons.org/431869399>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/431869399>	<http://www.w3.org/ns/prov#value>	"In FIG. 6, the shape of interfaces 138 and 140 can be something other than straight so that rays are directed as desired to the focus." .
<http://webisa.webdatacommons.org/prov/262421393>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/431869399> .
<http://webisa.webdatacommons.org/431869399>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<google.com> .