Paris, 29 September 1955 - Institutional correspondence Daniel-Henry Kahnweiler's letter to Willem Sandberg, dated 29 September 1955
Roxbury, 22 November 1955 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 22 November 1955
Amsterdam and Brussels, 1956 - Exhibition catalogue Guernica: avec 60 études et variantesGuernica: met 60 studies et varianten
1956 - Conferences and articles Text by Kahnweiler for the exhibition catalogue Guernica avec 60 études
Roxbury, 12 January 1956 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 12 January 1956
Paris, 22 May 1956 - Institutional correspondence Daniel-Henry Kahnweiler's letter to Willem Sandberg, dated 22 May 1956
19 July 1956 - Personal correspondence Daniel-Henry Kahnweiler's letter to Pablo Picasso, dated 19 July 1956