Flushing, New York, 23 May 1939 - Institutional correspondence Simon Guggenheim's and Dana C. Backus's form letter to ask for donations
Edinburgh, 25 January 1939 - Institutional correspondence Elizabeth Watt's letter to J.N. Duddington, dated 25 January 1939
Edinburgh, 7 April 1939 - Institutional correspondence Elizabeth Watt 's letter to J.N. Duddington, dated 7 April 1939