Ralph Waldo Emerson (2010). “Essays and English Traits by Ralph Waldo Emerson: The Five Foot Shelf of Classics, Vol. V (in 51 Volumes)”, p.133, Cosimo, Inc.
James Boswell, Samuel Johnson (1824). “The Life of Samuel Johnson, LL. D., Comprehending an Account of His Studies, and Numerous Works, in Chronological Order: A Series of His Epistolary Correspondence and Conversations with Many Eminent Persons; and Various Original Pieces of His Composition, Never Before Published; the Whole Exhibiting a View of Literature and Literary Men in Great Britain, for Near Half a Century During which He Flourished”, p.339