The vector map layers data, provided there, originated from Gazetteer of Planetary 
Nomenclature of International Astronomical Union (IAU) Working Group for Planetary 
System Nomenclature (WGPSN), which published on USGS site: 
http://planetarynames.wr.usgs.gov. The MOON_nomenclature.zip file was used from the site, 
which contains shape-file representation.
  The datum presented here in form of .VML-files (stands Vector Map Layer), 
which is proprietary compressed format of author of the datum.
  Additionally the datum contains data for both Polar Regions of Moon re-projected 
to Polar Stereographic projection. Areas of this re-projecting coincide with respective 
areas for raster elevation and albedo data of LOLA instrument of LRO mission for 
respective Polar Regions.

See site of author: www.runspect.com for more details.
Copyright (c) 2016 Yuri Feldman
