EPSG
Ordnance Survey of Great Britain and http://www.ngs.noaa.gov/ (NADCON readme file).
2008-06-24
Topographic mapping.
NADCON conversion program provides transformation from Puerto Rico Datum to NAD83 (original 1986 realization) but making the transformation appear to user as if from NAD27.
Puerto Rico, US Virgin Islands and British Virgin Islands - onshore.
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "GeodeticReferenceFrame", "name": "Puerto Rico", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 }, "scope": "Topographic mapping.", "area": "Puerto Rico, US Virgin Islands and British Virgin Islands - onshore.", "bbox": { "south_latitude": 17.62, "west_longitude": -67.97, "north_latitude": 18.78, "east_longitude": -64.25 }, "id": { "authority": "EPSG", "code": 6139 } }