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
Pars, 9 February 1955 - Institutional correspondence Pablo Picasso's letter to Alfred H. Barr Jr., dated 9 February 1955
Amsterdam and Brussels, 1956 - Exhibition catalogue Guernica: avec 60 études et variantesGuernica: met 60 studies et varianten
Berlin, 1975 - Exhibition catalogue Exhibition catalogue for Kunst und Politik am Beispiel Guernica. Picasso und der Spanische Bürgerkrieg
New York, 31 August 1981 - Institutional correspondence John Koegel's letter to Richard E. Oldenburg, dated 31 August 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
30 October 1981 - Institutional correspondence John Koegel's letter to Richard E. Oldenburg, dated 30 October 1981