Sigmar Polke (Oels 1941 – 2010 Cologne). ”GUTE NACHT”. 1960s Ballpoint pen on paper. 29,5 × 21 cm (11 ⅝ × 8 ¼ in.). Titled at the top: GUTE NACHT. [3390] Provenance: Private Collection, Rhineland (acquired at Galerie Borgmann, Cologne) We would like to thank Michael Trier, Cologne, for kindly providing additional information