Drucker, P. F. (1971). New markets and other essays. Heinemann.
Chicago Style aipamenaDrucker, Peter F. New Markets and Other Essays. London: Heinemann, 1971.
MLA aipamenaDrucker, Peter F. New Markets and Other Essays. Heinemann, 1971.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.