Letter to William McKinley. "Diary and Letters of Rutherford Birchard Hayes: Nineteenth President of the United States". Book edited by Charles Richard Williams, The Ohio State Archaeological and Historical Society, December 27, 1892.
Robert Louis Stevenson (2015). “The Strange Case of Dr. Jekyll and Mr. Hyde (Classic Unabridged Edition): Psychological thriller by the prolific Scottish novelist, poet and travel writer, author of Treasure Island, Kidnapped, Catriona, The Black Arrow and A Child's Garden of Verses”, p.11, e-artnow