Helprin, M. Willis avenue: Mark Helprin. The city.(1979).
Lua i Stíl Chicago (17ú heag.)Helprin, Mark. "Willis Avenue: Mark Helprin." The City.(1979) .
Lua MLA (8ú heag.)Helprin, Mark. "Willis Avenue: Mark Helprin." The City.(1979), .
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.