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Lua i Stíl Chicago (17ú heag.)Ray, Gene. Joseph Beuys: Mapping the Legacy / Edited by Gene Ray. Essays by Lukas Beckmann. New York: D.A.P. [u.a.], 2001.
Lua MLA (8ú heag.)Ray, Gene. Joseph Beuys: Mapping the Legacy / Edited by Gene Ray. Essays by Lukas Beckmann. D.A.P. [u.a.], 2001.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.