Covey, S. R., Merrill, A. R., & Merrill, R. R. (1994). First things first: To live, to love, to learn, to leave a legacy. Free Press.
Citazione stile Chigago Style (17a edizione)Covey, Stephen R., A. Roger Merrill, e Rebecca R. Merrill. First Things First: To Live, to Love, to Learn, to Leave a Legacy. New York: Free Press, 1994.
Citatione MLA (9a ed.)Covey, Stephen R., et al. First Things First: To Live, to Love, to Learn, to Leave a Legacy. Free Press, 1994.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.