One thing that was not mentioned in article (searched for "OSM" and "OpenStreetMap"): building data and maybe also some other info is from OpenStreetMap. BTW,

One thing that was not mentioned in article (searched for "OSM" and "OpenStreetMap"): building data and maybe also some other info is from OpenStreetMap. BTW, OpenStreetMap data is available for anyone as long they credit it (there are some additional rules about merging it with other databases) - see https://www.openstreetmap.org/ https://www.openstreetmap.org/ for place where you may see just part of dataset and contribute.