Gaya APA
Kouzes, J, M., Posner, B, Z.
(2007).
The leadership challenge
(
4th ed)
.
United States of America:
Jossey-bass.
Gaya MLA
Kouzes, James, M.., Posner, Barry, Z..
"The leadership challenge".
4th ed
United States of America:
Jossey-bass,
2007.
.