APA aipamena

M.Walker Robert. (1966). The world around you. New York: A Ladder Edition.

Chicago Style aipamena

M.Walker Robert. The World Around You. New York: A Ladder Edition, 1966.

MLA aipamena

M.Walker Robert. The World Around You. New York: A Ladder Edition, 1966.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.