Παραπομπή APA
Drucker, P. F. 1. (2005). The essential Drucker: The best of sixty years of Peter Drucker's essential writings on management. New York: Collins Business Essentials.
Παραπομπή Chicago StyleDrucker, Peter F. 1909-2005. The Essential Drucker: The Best of Sixty Years of Peter Drucker's Essential Writings On Management. New York: Collins Business Essentials, 2005.
Παραπομπή MLADrucker, Peter F. 1909-2005. The Essential Drucker: The Best of Sixty Years of Peter Drucker's Essential Writings On Management. New York: Collins Business Essentials, 2005.
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