Scientific correspondence, 1897-1900
Scientific correspondence, 1897-1900
Letter, 7 March 1899
Letter, 12 March 1899
Letter, 13 April 1899
Letter, 21 May 1899
Letter, 7 September 1899
Letter, 18 December 1899
Letter, 15 March 1899
Letter, 10 August 1899
Letter, 7 March 1899