Heinz Mack "HOMAGE À STEINWAY & SONS" (1960/62) Oil on canvas Signed and dated in pencil on the reverse: mack 60/62. Titled in black brush on the stretcher: "Homage à Steinway & Sons" 140 x 200 cm Private collection, Berlin Mack Piene Uecker. Krefeld, Museum Haus Lange, 1963 / Ausstellung des Westdeutschen Künstlerbunds. Hagen, Karl-Ernst-Osthaus-Museum, 1964 There, also a label of the exhibitions Krefeld 1963 and Hagen 1964 (see below)