Cita APA (7th ed.)

Covey, S. (1992). The seven habits of highly effective people. Simon & Schuster.

Cita Chicago (17th ed.)

Covey, Stephen. The Seven Habits of Highly Effective People. London: Simon & Schuster, 1992.

Cita MLA (9th ed.)

Covey, Stephen. The Seven Habits of Highly Effective People. Simon & Schuster, 1992.