APA (7th ed.) Zitazioa
(1980). The 1980 world book year book (ed.). World book- childcraft international, Inc..
Chicago Style (17th ed.) Zitazioa
The 1980 World Book Year Book. ed. Chicago: World book- childcraft international, Inc., 1980.
MLA (9th ed.) Zitazioa
The 1980 World Book Year Book. ed. World book- childcraft international, Inc., 1980.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.