Catalogue published for the exhibition organized by the Guggenheim Museum Bilbao and the Râeunion des Musâees Nationaux-Grand Palais, with the participation of the Niki Charitable Art Foundation, Santee. Held at the Grand Palais, Galeries Nationales, Paris, France, September 17, 2014-February 2, 2015 and Guggenheim Museum, Bilbao, Spain, February 27-June 11, 2015.