London, J. (2006). The iron heel. Penguin Books.
Lua i Stíl Chicago (17ú heag.)London, Jack. The Iron Heel. New York: Penguin Books, 2006.
Lua MLA (9ú heag.)London, Jack. The Iron Heel. Penguin Books, 2006.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.