Madrid, 6 December 1968 - Institutional correspondence Luis Carrero Blanco's letter to Florentino Pérez Embid
Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to Pablo Picasso
Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to Daniel-Henry Kahnweiler
Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to the Museum of Modern Art, New York
New York, 4 May 1950 - Institutional correspondence Joseph Schwartz's letter to the Museum of Modern Art, New York