Cita APA (7th ed.)

COVEY STEPHEN R. (1995). PRINCIPLE CENTRED LEADERSHIP. SIMON & SCHUSTER INC.

Cita Chicago (17th ed.)

COVEY STEPHEN R. PRINCIPLE CENTRED LEADERSHIP. LONDON: SIMON & SCHUSTER INC, 1995.

Cita MLA (9th ed.)

COVEY STEPHEN R. PRINCIPLE CENTRED LEADERSHIP. SIMON & SCHUSTER INC, 1995.