United States. Central Intelligence Agency. The 1998 CIA World Factbook.
Chicago Style (17th ed.) ZitazioaUnited States. Central Intelligence Agency. The 1998 CIA World Factbook.
MLA (9th ed.) ZitazioaUnited States. Central Intelligence Agency. The 1998 CIA World Factbook.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.