Samuel Richardson (1755). “A collection of the moral and instructive sentiments, maxims, cautions, and reflexions, contained in the histories of Pamela, Clarissa, and Sir Charles Grandison: Digested under proper heads, with references to the volume, ...”, p.19
Thomas Hobbes (1750). “The Moral and Political Works of Thomas Hobbes of Malmesbury: Never Before Collected Together : To which is Prefixed, the Author's Life, Extracted from that Said to be Written by Himself, ...”, p.145
Dr. Robert C. Worstell, Claude C. Hopkins (2014). “Scientific Advertising - Masters of Marketing Secrets: From the First Great Copywriter”, p.75, Lulu.com