New York, 10 February 1956 - Institutional correspondence A letter from Louise A. Boyer to Petro (Nelly) Van Doesburg
New York, 14 November 1939 - Institutional correspondence Nelson Rockefeller's telegram to Pablo Picasso
Museo Nacional Centro de Arte Reina Sofía, Madrid, October 19, 2018 - Interview Francis Frascina in conversation with Lucy Lippard