The design for this window, in pastels, is in a private collection in southern Germany (see PDF below)

The window was part of the estate of the Düsseldorf artist Maria Sichtermann Wernze (1907–2000), and has been dated by Dr Alexander Klee of Vienna to c.1930. Klee has authenticated this window and sees this, together with the pastel, as a preparatory work for the windows of of 1932/33 for the Pelikan factory in Hannover, and so does Ulrich Röthke (of the Brandenburgische Technische Universität, Cottbus), who is writing a doctorate on Adolf Hölzel’s architectural glass-painting.

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