Halgmann, B. (1998). Frottage - shaping the ungraspable: Birgit Halgmann. Issues in contemporary culture and aesthetics.
Chicago-viite (17. p.)Halgmann, Birgit. "Frottage - Shaping the Ungraspable: Birgit Halgmann." Issues in Contemporary Culture and Aesthetics 1998.
MLA-viite (8. p.)Halgmann, Birgit. "Frottage - Shaping the Ungraspable: Birgit Halgmann." Issues in Contemporary Culture and Aesthetics, 1998.
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