Sources: NNU-F
- SLC to Unidentified, 5 June 1886 · Hartford, Conn · UCCL03406
- SLC to Walter Q. Gresham, 6 April 1893 · New York, N.Y · UCCL04549
- SLC to Elizabeth Robins, 30 July 1899 · Sanna, Sweden · UCCL11465
- SLC to Unidentified, 11 November 1899 · London, England · UCCL05705
- SLC to John Y. MacAlister, 23 March 1900 · London, England · UCCL11713
- SLC to William Martin Conway, 1 April 1900 · London, England · UCCL05730
- SLC to Eleanor Bridge, 12 June 1900 · London, England · UCCL11709
- SLC to Elizabeth Robins, 25 March 1904 · Florence, Italy · UCCL06816
- SLC per Isabel V. Lyon to Elizabeth Robins, 31 March 1904 · Florence, Italy · UCCL11714
- SLC to Frank H. Mason, 30 September 1905 · Unknown place · UCCL11715
- SLC to Frederick A. Duneka, 24 February 1906 · New York, N.Y · UCCL11716
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