Charles Proteus Steinmetz, Joseph Le Roy Hayden (1917). “Steinmetz Electrical Engineering Library: Engineering mathematics; a series of lectures delivered at Union college (3rd ed. 1917)”
"Comedian Dylan Moran: 'What am I looking forward to? Incontinence and memory loss'". Interview with Nosheen Iqbal, www.theguardian.com. December 22, 2009.
Henry Moseley's letter to Margery Moseley (February 2, 1913), as quoted in "H. G. J. Moseley: The Life and Letters of an English Physicist 1887-1915" edited by J. L. Heilbron (p. 201), 1974.