On 11 July 1942 Adler, who was Jewish, was deported to the extermination campAuschwitz, where, judged too old to work, he was killed soon afterwards. There is a stolperstein in his memory at his last place of employment in Hamburg.
Leonhardt, Brigitte; Dieter Zühlsdorff and Norbert Götz (1994). Friedrich Adler - Zwischen Jugendstil und Art Déco (in German). Stuttgart: Arnoldsche Art Publishers. ISBN978-3-925369-34-6.Cite uses deprecated parameters (help)
Schäll, Ernst (2004). Friedrich Adler. Leben und Werk (in German). Bad Buchau: Federsee-Verlag. ISBN3-925171-58-4.