Covey, S. R. (2020). 7 Habits of Highly Effective People. Simon and Schuster.
Lua i Stíl Chicago (17ú heag.)Covey, Stephen R. 7 Habits of Highly Effective People. New Delhi: Simon and Schuster, 2020.
Lua MLA (9ú heag.)Covey, Stephen R. 7 Habits of Highly Effective People. Simon and Schuster, 2020.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.