From Citizendium - Reading time: 1 min
Smith Family Papers, Vermont Farm Bureau Papers, The Bailey/Howe Library, University of Vermont Libraries Special Collections, University of Vermont, Burlington, Vermont.
J. Gregory Smith (1818-1891) Papers, 1810-1928, (bulk 1845-1899), Leahy Library, Vermont Historical Society, Barre, Vermont.
Vermont Central Railroad Records, 1849-1880, Leahy Library, Vermont Historical Society, Barre, Vermont.
Dowden, Albert Ricker. "John Gregory Smith." Vermont History 32, no. 2 (April 1964): 78-97.
Lubetkin, M. John. Jay Cooke's Gamble: The Northern Pacific Railroad, the Sioux, and the Panic of 1873. Norman: University of Oklahoma Press, 2006.
National Governors Association, "John Gregory Smith," 2015.
Sobel, Robert, and John Raimo, eds. Biographical Directory of the Governors of the United States, 1789-1978, Vol. 4. Westport, CT: Meckler Books, 1978. 4 vols.
The National Cyclopaedia of American Biography, Vol. 8. New York: James T. White & Company.
Ullery, Jacob G., Men of Vermont: An Illustrated Biographical History. Brattleboro, VT: Transcript Publishing Company, 1894, Part I, p. 96.