APA
Drucker P. F., . (2009). Managing in a time of great change. Boston, Mass: Harvard Business Press.
Chicago
Drucker Peter F, . 2009. Managing in a time of great change. Boston, Mass: Harvard Business Press.
Harvard
Drucker P. F., . (2009). Managing in a time of great change. Boston, Mass: Harvard Business Press.
MLA
Drucker Peter F, . Managing in a time of great change. Boston, Mass: Harvard Business Press. 2009.