Palen, J. J. (1992). The urban world (4th ed.). McGraw - Hill.
Lua i Stíl Chicago (17ú heag.)Palen, John J. The Urban World. 4th ed. New York: McGraw - Hill, 1992.
Lua MLA (9ú heag.)Palen, John J. The Urban World. 4th ed. McGraw - Hill, 1992.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.