Mainz, 20 July 1955 - Institutional correspondence A letter from J. Mougin to Jacques Guerin, dated 20 July 1955
Mainz, 13 October 1955 - Institutional correspondence J. Mougin's letter to François Mathey, dated 13 October 1955
Mainz, 18 October 1955 - Institutional correspondence J. Mougin's letter to Jacques Guerin, dated 18 October 1955
Mainz, 2 May 1956 - Institutional correspondence J. Mougin's letter to François Mathey, dated 2 May 1956
New York, 5 November 1938 - Institutional correspondence Herman F. Reissig's letter to Julius Perlstein
New York, 1 November 1939 - Institutional correspondence Herman F. Reissig's letter to Marcelene Peterson, dated 1 November 1939
New York, 2 November 1939 - Institutional correspondence Herman F. Reissig's letter to Milton Wichner
New York, 17 November 1939 - Institutional correspondence Herman F. Reissig's letter to Marcelene Peterson, dated 17 November 1939