Cita APA (7a ed.)

Drucker, P. F. (2002). Management challenges for the 21st century (EPub ed.). HarperCollins Publishers.

Cita Chicago Style (17a ed.)

Drucker, Peter F. Management Challenges for the 21st Century. EPub ed. Pymble, N.S.W. ; New York, N.Y.: HarperCollins Publishers, 2002.

Cita MLA (9a ed.)

Drucker, Peter F. Management Challenges for the 21st Century. EPub ed. HarperCollins Publishers, 2002.