11. Letter from R.W. Simpson to Thomas G. Clemson, 1882 January 11 Institution: Clemson University Libraries
12. Letter from Mary C. Rion to Major R. W. Simpson, 1888 May 7 Institution: Clemson University Libraries
13. Letter from A. G. Holmes, Jr. to Captain Richard Simpson, 1887 August 9 Institution: Clemson University Libraries