About: http://webisa.webdatacommons.org/285815742

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	Vector charts, however, are ???layered??? with types of information grouped together, following an international protocol (S-57)???depths in one layer, bottom characteristics in another layer, other navigational objects in another.
http://www.w3.org/ns/prov#wasQuotedFrom	practical-sailor.com