APA Style
Covey, Stephen R.. (1990).
Principle centered Leadership .
America:
Simon & Schuster.
Chicago Style
Covey, Stephen R..
Principle centered Leadership.
America:
Simon & Schuster,
1990.
Text.
MLA Style
Covey, Stephen R..
Principle centered Leadership.
America:
Simon & Schuster,
1990.
Text.
Turabian Style
Covey, Stephen R..
Principle centered Leadership.
America:
Simon & Schuster,
1990.
Print.