Polke, Sigmar Untitled Signed and dated in pencil lower right: Sigmar Polke 98. Signed and dated on the reverse with felt-tip pen in black: Sigmar Polke 98 Private collection, Rhineland (acquired at Galerie Erhard Klein, Bonn) 100 x 70 cm 39 3/8 x 27 1/2 in. Interferenzfarbe auf schwarz grundiertem Karton 1998