RIES AL. (1989). BOTTOM - UP MARKETING. MCGRAW-HILL.
Chicago Style aipamenaRIES AL. BOTTOM - UP MARKETING. NEW YORK: MCGRAW-HILL, 1989.
MLA aipamenaRIES AL. BOTTOM - UP MARKETING. MCGRAW-HILL, 1989.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.