Posner, R. A. (1993). The problems of jurisprudence. Universal.
Chicago Style aipamenaPosner, Richard A. The Problems of Jurisprudence. N.Delhi: Universal, 1993.
MLA aipamenaPosner, Richard A. The Problems of Jurisprudence. Universal, 1993.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.