"Cargo Cult Science". Richard P. Feynman's Caltech commencement address (1974), as quoted in "'Surely You're Joking, Mr. Feynman!': Adventures of a Curious Character" edited by Ralph Leighton (p. 342), calteches.library.caltech.edu. 1985.
Richard P. Feynman, Robert B. Leighton, Matthew Sands (2015). “The Feynman Lectures on Physics, Vol. II: The New Millennium Edition: Mainly Electromagnetism and Matter”, p.71, Hachette UK
Richard P. Feynman's letter to Koichi Mano (February 3, 1966), as quoted in "Perfectly Reasonable Deviations from the Beaten Track: The Letters of Richard P. Feynman" edited by Michelle Feynman and Timothy Ferris (pp. 198, 201), April 5, 2005; also quoted in "Wise Man" by Freeman Dyson, www.nybooks.com. October 20, 2005.
Richard P. Feynman, Robert B. Leighton, Matthew Sands (2015). “The Feynman Lectures on Physics, Vol. II: The New Millennium Edition: Mainly Electromagnetism and Matter”, p.678, Basic Books