| USCENSUSAREA*http://www.census.gov/population/www/censusdata/density.html | |
| USCENSUSPOP*http://www.census.gov/population/cen2000/phc-t4/tab01.xls | |
| USCENSUSBOUNDS*http://www.census.gov/geo/www/cob/co2000.html | |
| ISO3166_1*https://www.cia.gov/library/publications/the-world-factbook/ | |
| ISO3166_2*https://www.cia.gov/library/publications/the-world-factbook/ |