APA (7th ed.) Citation

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

Chicago Style (17th ed.) Citation

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

MLA (8th ed.) Citation

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

Warning: These citations may not always be 100% accurate.