Gottfried Brockmann, The Existence of a Cripple, No. 4 (Krüppeldasein IV), (1922–23), Gouache on board, The Museum of Modern Art, New York. https://dartabase.art/cite/moma/34596

Gottfried Brockmann, The Existence of a Cripple, No. 1 (Krüppeldasein I), (1922–23), Gouache on board, The Museum of Modern Art, New York. https://dartabase.art/cite/moma/34612