organized by the Fondation Beyeler, Riehen/Basel, and the Kunstsammlung Nordrhein-Westfalen, Düsseldorf, in cooperation with the Kunstmuseum Den Haag, The Hague ; edited by Sam Keller and Ulf Küster for the Fondation Beyeler, as well as Susanne Gaensheimer, Kathrin Beßen, and Susanne Meyer-Büser for the Kunstsammlung Nordrhein-Westfalen