Avantgarde in Siegen. Die Galerie Nohl 1957 – 1968
Karl Riha
Kunstverein Siegen, 1994 ⁄ softcover
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Concrete Poetry : An Exhibition in Four Parts
Alvin Balkind
The Fine Arts Gallery, University of British Columbia, Vancouver, 1969 ⁄ 3 color folders with folding posters + 25 loose sheets in 3 panel cardboard folder