Letter, 1 February 1890
Letter, 3 April 1889
Letter from Otto Hahn to B.J. Harrington, written from toronto.
Letter, 2 March 1876
Letter, 11 January 1911
Letter, 6 July 1871
Letter, 5 August 1880
Letter, 4 September 1888
Letter, 10 January
Letter from M. Wilson