M. Scott Peck (2002). “The Road Less Traveled, 25th Anniversary Edition: A New Psychology of Love, Traditional Values, and Spiritual Growth”, p.75, Simon and Schuster
"Margaret Mead, 1901-1978: One of the Most Famous Anthropologists in the World". Voice of America Special English: "People in America" with Steve Ember and Shirley Griffith, learningenglish.voanews.com. July 1, 2011.
United States. President (1929-1933 : Hoover), Herbert Hoover, United States. Office of the Federal Register (1974). “Herbert Hoover: Containing the public messages, speeches, and statements of the President”