Frederick Winslow Taylor (1947). “Scientific Management, Comprising Shop Management: The Principles of Scientific Management [and] Testimony Before the Special House Committee”, New York, Harper
Josh Billings (1972). “Uncle Sam's Uncle Josh: Or, Josh Billings on Practically Everything, Distilled from Josh's Rum and Tansy New England Wit by Donald Day”
George Mason's letter to his daughter Sarah Mason McCarty after the death of an infand daughter (February 10, 1785) as quoted in Kate Mason Rowland "The Life of George Mason, Volume 2: 1725-1792" (p. 74), 1892.
John Wilkins (1802). “The Mathematical and Philosophical Works of the Right Rev. John Wilkins, Late Lord Bishop of Chester: To which is Prefix'd the Author's Life, and an Account of His Works; in Two Volumes”, p.134