Benjamin Franklin (1836). “The Works of Benjamin Franklin; Containing Several Political and Historical Tracts Not Included in Any Former Edition, and Many Letters, Official and Private, Not Hitherto Published; with Notes and a Life of the Author”, p.2
"Science, Philosophy and Religion, A Symposium". Book published by the Conference on Science, Philosophy and Religion in Their Relation to the Democratic Way of Life, Inc., New York, 1941.