APA aipamena

(1974). Petroleum in the 1970s. New York: United States.

Chicago Style aipamena

Petroleum in the 1970s. New York: United States, 1974.

MLA aipamena

Petroleum in the 1970s. New York: United States, 1974.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.