"Against a rigid and authoritarian art. "Dies alles, Herzchen, wird einmal dir geh?ren"--"All these, little darling, will one day be yours"--was the motto of a legendary event held in Frankfurt in 1967: Charlotte Posenenske (1930-1985) had her corrugatedcardboard square tubing arranged in perpetually changing structures. In memory of the internationally renowned conceptual artist, a similar performance was staged at Kunsthalle Lingen, Germany, on...