APA aipamena

(1987). The New Encyclopaedia Britannica Volume 9 Alphabetic [O-P-Q-R]. The University of Chicago.

Chicago Style aipamena

The New Encyclopaedia Britannica Volume 9 Alphabetic [O-P-Q-R]. The University of Chicago, 1987.

MLA aipamena

The New Encyclopaedia Britannica Volume 9 Alphabetic [O-P-Q-R]. The University of Chicago, 1987.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.