Halgmann, B. (1998). Frottage - shaping the ungraspable: Birgit Halgmann. Issues in contemporary culture and aesthetics.
Lua i Stíl Chicago (17ú heag.)Halgmann, Birgit. "Frottage - Shaping the Ungraspable: Birgit Halgmann." Issues in Contemporary Culture and Aesthetics 1998.
Lua MLA (8ú heag.)Halgmann, Birgit. "Frottage - Shaping the Ungraspable: Birgit Halgmann." Issues in Contemporary Culture and Aesthetics, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.