Paris, 28 October 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 28 October 1953
Paris, 5 November 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 5 November 1953
New York, 12 March 1956 - Institutional correspondence Bernard Karpel's letter to Willem Sandberg, dated 12 March 1956
New York, 27 November 1956 - Institutional correspondence Bernard Karpel's letter to Willem Sandberg, dated 27 November 1956