Covey, S. R. (1989). The seven habits of highly effective people: Restoring the character ethic. Simon and Schuster.
Chicago-referens (17:e uppl.)Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. New York: Simon and Schuster, 1989.
MLA-referens (8:e uppl.)Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. Simon and Schuster, 1989.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.