C. O. Muller has
been in two exhibitions at MoMA,
between 1936 and 1941.
2 March to 19 April 1936
Pablo Picasso, Henri Matisse, Joan Miró and Paul Klee, among others, were involved.
11–26 June 1941
Max Ernst, Ben Shahn, Henri de Toulouse-Lautrec and Herbert Bayer, among others, were involved.