APA aipamena

(2008). Info USA 2007-2008: Your guide to the USA. United States.

Chicago Style aipamena

Info USA 2007-2008: Your Guide to the USA. United States, 2008.

MLA aipamena

Info USA 2007-2008: Your Guide to the USA. United States, 2008.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.