Hagen, U. (1991). A challenge for the actor. Maxwell Macmillan International.
Lua i Stíl Chicago (17ú heag.)Hagen, Uta. A Challenge for the Actor. New York: Maxwell Macmillan International, 1991.
Lua MLA (9ú heag.)Hagen, Uta. A Challenge for the Actor. Maxwell Macmillan International, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.