Ries, A. (1990). Bottom up marketing. Penguin (Plume).
Chicago Style aipamenaRies, Al. Bottom Up Marketing. New York: Penguin (Plume), 1990.
MLA aipamenaRies, Al. Bottom Up Marketing. Penguin (Plume), 1990.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.