Karl Schmidt-Rottluff. 'Tower behind trees' artist's postcard, 1911. Colour crayons over ink on stamped postcards, addressed and dedicated to Dr. Elsa Hopf, Hamburg. Stamped: Dangast (...)1911. 14.4 x 9.3 cm. Verso handwritten by the artist: Frau Dr. Elsa Hopf Hamburg Bieber Str 3/5 Vielmals herzl. Gruesse Ihr S-Rottluff. Dangast - Nordsee." Starting Price : 12000