Oliver Goldsmith (1871). “The works of Oliver Goldsmith: Vicar of Wakefield, select poems and comedies, with intr., notes and a life by J.F. Waller”, p.209
David Hume, Eric Steinberg (1993). “An Enquiry Concerning Human Understanding ; [with] A Letter from a Gentleman to His Friend in Edinburgh ; [and] An Abstract of a Treatise of Human Nature”, p.71, Hackett Publishing
Cassandra Clare (2011). “Cassandra Clare: The Mortal Instrument Series (4 books): City of Bones; City of Ashes; City of Glass; City of Fallen Angels”, p.859, Simon and Schuster
Wallace D. Wattles (2015). “The Science of Being Great: Personal Self-Help Book of Wallace D. Wattles (Unabridged): From one of The New Thought pioneers, author of The Science of Getting Rich, The Science of Being Well, How to Get What You Want, Hellfire Harrison, How to Promote Yourself and A New Christ”, p.39, e-artnow