एपीए उद्धरण

Covey, S. R. (1991). Principle centered leadership. New York: A Fireside.

शिकागो स्टाइल उद्धरण

Covey, Stephen R. Principle Centered Leadership. New York: A Fireside, 1991.

एमएलए उद्धरण

Covey, Stephen R. Principle Centered Leadership. New York: A Fireside, 1991.