Covey, S. R. (2002). First Things First. Pocket Books Ltd.
Lua i Stíl Chicago (17ú heag.)Covey, Stephen R. First Things First. London: Pocket Books Ltd, 2002.
Lua MLA (9ú heag.)Covey, Stephen R. First Things First. Pocket Books Ltd, 2002.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.