translation: "Leiden Theatre; Wednesday 14 February 8 p.m.; Grand Dada Night; Kurt Schwitters, Mrs. Petro van Doesburg, Theo van Doesburg; Entrance: f2,-, f1.50, f1.- rights excluded. 1573; Advance bookings with Mr. Van Zwicht, Breestr., and on day of performance 10 [a.m.]-2 [p.m.] at the theatre.
Unknown author<span style="display: none;">Unknown author</span>
1923-02
Holland's bankroet door dada. Documenten van een dadaïstische triomftocht door Nederland. Amsterdam: Ravijn, 1995 (<a href="//commons.wikimedia.org/wiki/Special:BookSources/9072768418" title="Special:BookSources/9072768418">ISBN 9072768418</a>): p. 61.