Frieling, R. The art of participation: 1950 to now.
Lua i Stíl Chicago (17ú heag.)Frieling, Rudolf. The Art of Participation: 1950 to Now.
Lua MLA (8ú heag.)Frieling, Rudolf. The Art of Participation: 1950 to Now.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.