Covey, S. R. (1999). Seven habits of highly effective people (1st.). Pocket books.
Citación estilo ChicagoCovey, Stephen R. Seven Habits of Highly Effective People. 1st. London: Pocket books, 1999.
Cita MLACovey, Stephen R. Seven Habits of Highly Effective People. 1st. Pocket books, 1999.
Warning: These citations may not always be 100% accurate.