APA aipamena

Drucker, P. F. (1999). Management challenges for the 21st century (First edition.). HarperBusiness.

Chicago Style aipamena

Drucker, Peter F. Management Challenges for the 21st Century. First edition. New York: HarperBusiness, 1999.

MLA aipamena

Drucker, Peter F. Management Challenges for the 21st Century. First edition. HarperBusiness, 1999.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.