Covey, S. R. (2004). The seven habits of highly effective people ([2nd ed.].). Pocket Books.
Cita Chicago Style (17a ed.)Covey, Stephen R. The Seven Habits of Highly Effective People. [2nd ed.]. London: Pocket Books, 2004.
Cita MLA (9a ed.)Covey, Stephen R. The Seven Habits of Highly Effective People. [2nd ed.]. Pocket Books, 2004.
Precaución: Estas citas no son 100% exactas.