"And I Quote, Revised Edition: The Definitive Collection of Quotes, Sayings, and Jokes for the Contemporary Speechmaker". Book by Andrew Frothingham, Ashton Applewhite, and Tripp Evans, p.469, 1992.
Aldo Leopold (2013). “Aldo Leopold: A Sand County Almanac & Other Writings on Conservation and Ecology: (Library of America #238)”, p.112, Library of America
Marie Curie's instructions regarding a proposed gift of a wedding dress for her marriage to Pierre in July 1895, as quoted in Eve Curie Labouisse "Madame Curie: A Biography" translated by Vincent Sheean (p. 137), 1937.