Charles Lyell (1863). “The Geological Evidences of the Antiquity of Man with Remarks on Theories of the Origin of Species by Variation by Charles Lyell”, p.421
"Reviewing Mr g: Physicist-turned-novelist Alan Lightman meets God at the intersection of science and religion". Interview With Greg Quill, www.thestar.com. February 12, 2012.
Wallace D. Wattles (2015). “Wallace D. Wattles Ultimate Collection – 10 Books in One Volume: The Science of Getting Rich, The Science of Being Well, The Science of Being Great, How to Get What You Want and more: From one of the New Thought pioneers, author of Making of the Man Who Can or How to Promote Yourself and New Science of Living and Healing or Health Through New Thought and Fasting”, p.38, e-artnow