Gaya APA
COVEY, Stephen R.. (1991).
Principle-centered leadership .
United Kingdom:
Simon & Schuster.
Gaya Chicago
COVEY, Stephen R..
Principle-centered leadership.
United Kingdom:
Simon & Schuster,
1991.
Text.
Gaya MLA
COVEY, Stephen R..
Principle-centered leadership.
United Kingdom:
Simon & Schuster,
1991.
Text.
Gaya Turabian
COVEY, Stephen R..
Principle-centered leadership.
United Kingdom:
Simon & Schuster,
1991.
Print.