Graham, Cooper C.; Higgins, Steve; Mancini, Elaine; Viera, João Luiz. Entry for "A Sound Sleeper", D. W. Griffith and the Biograph Company. Metuchen, New Jersey and London: The Scarecrow Press, 1985, p. 44. Internet Archive. Retrieved 6 March 2021.
Arvidson, Linda. When the Movies Were Young. New York: Dover Publications, 1969 (reprint of 1925 publication), p. 59. Internet Archive. Retrieved 8 March 2021.
Lawrence, Florence (in collaboration with Monte K. Katterjohn). "Growing Up with the Movies", part three of four, Photoplay (Chicago), January 1915, p. 105. Internet Archive, San Francisco, California. Retrieved 2 March 2021.
"'A Sound Sleeper'", The Moving Picture World, 17 April 1909, p. 476. Internet Archive. Retrieved 8 March 2021.
Greason, Alfred (pen name "Rush"). "NOTES / "'A Sound Sleeper."Variety (Manhattan, New York), 17 April 1909, p. 12. Internet Archive. Retrieved 5 March 2021.
European Film Gateway, a centralized on-line access and referral point to the holdings of film archives throughout the European Union. Retrieved January 14, 2020.
filmpreservation.org
"Nitrate Degradation", National Film Preservation Foundation (NFPF), San Francisco, California. Retrieved 5 March 2021.
hathitrust.org
babel.hathitrust.org
Niver, Kemp R. Early Motion Pictures: The Paper Print Collection in the Library of Congress, "A Sound Sleeper. Washington, D.C.: Motion Picture, Broadcasting, and Recorded Sound Division, 1985, p. 306. HathiTrust Digital Library. Retrieved 8 March 2021.
