Mougins, 14 November 1970 - Institutional correspondence Pablo Picasso's letter to the New York's Museum of Modern Art
Paris, 3 October 1948 - Institutional correspondence Pablo Picasso's letter to Alfred H. Barr Jr., dated 3 October 1948
Meudon, 19 November 1955 - Institutional correspondence Nelly Van Doesburg's letter to Louise Boyer, dated 19 November 1955
Pars, 9 February 1955 - Institutional correspondence Pablo Picasso's letter to Alfred H. Barr Jr., dated 9 February 1955
Meudon, 19 November 1955 - Institutional correspondence Nelly Van Doesburg's letter to Louise Boyer, dated 19 November 1955
Meudon, 29 December 1955 - Institutional correspondence Nelly Van Doesburg's letter to Louise Boyer, dated 29 December 1955
Amsterdam and Brussels, 1956 - Exhibition catalogue Guernica: avec 60 études et variantesGuernica: met 60 studies et varianten
Meudon, 13 February 1956 - Institutional correspondence Petro (Nelly) Van Doesburg's letter Alfred H. Barr Jr.
Berlin, 1975 - Exhibition catalogue Exhibition catalogue for Kunst und Politik am Beispiel Guernica. Picasso und der Spanische Bürgerkrieg