Milan, 4 August 1953 - Institutional correspondence A letter from Fernanda Wittgens to Willem Sandberg, dated 4 August 1953
Milan, 12 August 1953 - Institutional correspondence Fernanda Wittgens' letter to Willem Sandberg, dated 12 August 1953
Milan, 7 October 1953 - Institutional correspondence A letter from Fernanda Wittgens to Willem Sandberg, dated 7 October 1953
Paris, 6 September 1939 - Institutional correspondence Christian Zervos's letter to Alfred H. Barr Jr., dated 6 September 1939
Paris, 27 December 1939 - Institutional correspondence Christian Zervos's letter to Alfred H. Barr Jr., dated 27 December 1939
Paris, 26 October 1939 - Institutional correspondence Christian Zervos's letter to Alfred H. Barr Jr., dated 26 October 1939