George Washington, John Jay, Jared Sparks (1850). “Washington's Farewell Address to the People of the United States of America”, p.46, New York : J. Wiley
"Quote Junkie: Greek and Roman : An Interesting Collection of Quotes from the Greatest Greek and Roman Philosophers and Leaders". Book edited by the Hagopian Institute, p. 62, 2008.
George MacDonald (2015). “The Complete Novels of George Macdonald (Illustrated): The Princess and the Goblin, The Princess and Curdie, Phantastes, At the Back of the North Wind, Lilith, David Elginbrod, Malcolm, Ranald Bannerman's Boyhood, Wilfrid Cumbermede and many more”, p.7592, e-artnow