(2005). Regulation (2006 ed. textbook.). Becker Professional Review.
Chicago Style aipamenaRegulation. 2006 ed. textbook. Oakbrook Terrace, Illinois: Becker Professional Review, 2005.
MLA aipamenaRegulation. 2006 ed. textbook. Becker Professional Review, 2005.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.