Dyfyniad APA

Drucker, P. F. (1999). Management challenges for the 21st century. Butterworth-Heinemann.

Dyfyniad Arddull Chicago

Drucker, Peter F. Management Challenges for the 21st Century. Oxford: Butterworth-Heinemann, 1999.

Dyfyniad MLA

Drucker, Peter F. Management Challenges for the 21st Century. Butterworth-Heinemann, 1999.

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