APA (7th ed.) Zitazioa
Hills, G. Rock of Contention: A History of Gibraltar. Robert Hale.
Chicago Style (17th ed.) Zitazioa
Hills, George. Rock of Contention: A History of Gibraltar. Londres, Inglaterra: Robert Hale.
MLA (9th ed.) Zitazioa
Hills, George. Rock of Contention: A History of Gibraltar. Robert Hale.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.