Drucker, P. F. (1999). Management challenges for the 21st century. Butterworth-Heinemann.
芝加哥风格引文Drucker, Peter F. Management Challenges for the 21st Century. Oxford: Butterworth-Heinemann, 1999.
MLA引文Drucker, Peter F. Management Challenges for the 21st Century. Butterworth-Heinemann, 1999.
警告：这些引文格式不一定是100％准确.