Until 1914 Jakob Soulek often carried out works for the Wiener Werkstätte which had out-sourced the furniture production very early. There was also a long-standing relationship between Hoffmann and Soulek. Hoffmann's influence on these two pieces is obvious: The strict architectonic structure and the carved wooden rosette on the door are all style elements which Hoffmann liked to use at the time. Even though they are unsigned, Soulek's authorship for this bookcase is very likely—the fittings, locks and workmanship all clearly point in this direction.