Cita APA (7a ed.)

Drucker, P. F. (2001). Management Challenges for the 21st Century. HarperCollins Publishers.

Cita Chicago Style (17a ed.)

Drucker, Peter F. Management Challenges for the 21st Century. New York: HarperCollins Publishers, 2001.

Cita MLA (9a ed.)

Drucker, Peter F. Management Challenges for the 21st Century. HarperCollins Publishers, 2001.