Citazione Stile APA (7a Edizione)

Covey, S. R. (1989). The seven habits of highly effective people: Restoring the character ethic. Simon and Schuster.

Citazione stile Chigago Style (17a edizione)

Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. New York: Simon and Schuster, 1989.

Citatione MLA (8a ed.)

Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. Simon and Schuster, 1989.