Gardner, J. W. (1993). On leadership: With a preface to the paperback edition. Free Press.
Lua i Stíl Chicago (17ú heag.)Gardner, John W. On Leadership: With a Preface to the Paperback Edition. New York: Free Press, 1993.
Lua MLA (8ú heag.)Gardner, John W. On Leadership: With a Preface to the Paperback Edition. Free Press, 1993.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.