Gaya APA

Koontz, H., Weihrich, H. (1990). Essentials of management (5th.ed.). New York: McGraw-Hill Pub.Co..

Gaya MLA

Koontz, Harold., Weihrich, Heinz. "Essentials of management". 5th.ed. New York: McGraw-Hill Pub.Co., 1990. Text.