A. & W.-D. Dube, Erich Heckel Das Graphische Werk, Vols. I-III, E. Rathenau, New York, 1964-1974, reproductions, vols. I-II copy nos. 196, from the edition of 600, vol. III from the edition of 800, original linen boards, vols. I-II with slipcases, 290 x 230 mm.; P. Vogt, Erich Heckel, A. Bongers Recklinghausen, 1965; and ten others on Heckel (14)