New York, 24 September 1954 - Institutional correspondence Alfred H. Barr Jr.'s letter to Roland Penrose, dated 24 September 1954
New York, 16 January 1957 - Institutional correspondence Alfred H. Barr Jr.'s letter to Roland Penrose, dated 16 January 1957
14 June 1973 - Personal correspondence Roland Penrose's letter to Alfred H. Barr and Margaret Scolari Barr