Beri,G.C. (2000). Marketing research (3rd ed.). T.M.H.
Chicago Style aipamenaBeri,G.C. Marketing Research. 3rd ed. New Delhi: T.M.H, 2000.
MLA aipamenaBeri,G.C. Marketing Research. 3rd ed. T.M.H, 2000.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.