Values for the term property in POI objects
publisher: this author is making content available on the web that may have been originally developed by others in whole or part
contributor: this is one of many authors, this term is usually used when there are multiple authors for a single POI property
editor: this author was responsible for editing the material of another who originally developed the content
start: the POI came into existence at this time
end: the POI stopped existing at this time
instant: the POI was known to exist at this time in this place. No information is guaranteed to be the same before or after this time.
primary: the canonical name value
secondary: an alternate name value of lesser importance or authority than the primary one. A POI might have a secondary label and no primary one if the most authoritative name exists in another repository.
center: the locus of the POI
navigation point: the location at which vehicles can enter. This should be used for driving, aircraft landing, or boat docking.
entrance: the location at which persons can enter.
see http://www.w3.org/2010/POI/documents/Core/core-20111216.html#relationship for definitions within:
see http://iana.org/assignments/link-relations/link-relations.xml for definitions author