| # | |
| DIVA*http://www.cipotato.org/DIVA/data/DataServer.asp?AREA=NER&THEME=_adm | |
| # | |
| CIA*https://www.cia.gov/cia/publications/factbook/geos/ng.html | |
| ISO3166_1*https://www.cia.gov/library/publications/the-world-factbook/ | |
| ISO3166_2*https://www.cia.gov/library/publications/the-world-factbook/ |