Ketzner, K. (1977). The Language of the World. Routledge & Kegan Paul.
Chicago Style aipamenaKetzner, Kenneth. The Language of the World. London: Routledge & Kegan Paul, 1977.
MLA aipamenaKetzner, Kenneth. The Language of the World. Routledge & Kegan Paul, 1977.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.