Covey, S. R. (2004). The 8th habit: From effectiveness to greatness. Simon & Schuster, New Delhi.
Cita Chicago (17th ed.)Covey, Stephen R. The 8th Habit: From Effectiveness to Greatness. Simon & Schuster, New Delhi, 2004.
Cita MLA (9th ed.)Covey, Stephen R. The 8th Habit: From Effectiveness to Greatness. Simon & Schuster, New Delhi, 2004.
Atenció: Aquestes cites poden no estar 100% correctes.