Berlin, 1975 - Photograph View of the exhibition Kunst und Politik am Beispiel Guernica Picasso und der Spanische Bürgerkrieg
Roxbury, 22 November 1955 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 22 November 1955
Roxbury, 12 January 1956 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 12 January 1956