Richard Salter Storrs (1875). “Conditions of Success in Preaching Without Notes: Three Lectures Delivered Before the Students of the Union Theological Seminary, New York, Januray 13, 20, 27: 1875; with an Appendix”, p.114
Bernard Berenson (1962). “The Bernard Berenson Treasury: A Selection from the Works, Unpublished Writings, Letters, Diaries, and Journals of the Most Celebrated Humanist and Art Historian of Our Times, 1887-1958”