Harriet Beecher Stowe (1811–1896) Abolitionist, author
The Pearl of Orr's Island : A Story of the Coast of Maine (1862).
Duhamel, Cours d'Analyse de l'Ecole Polytechnique. Paris, Bachelier. vol i 1841 vol. ii. 1840.
The Differential and Integral Calculus (1836)
Harriet Beecher Stowe (1811–1896) Abolitionist, author
The Pearl of Orr's Island : A Story of the Coast of Maine (1862).
Eleftherios Venizelos (1864–1936) Greek politician
Source: [Gibbons, H. A., Venizelos, Modern Statesmen Series, Houghton Mifflin Company, 1920, http://books.google.com/books?id=DVMlZtkx5bwC], p. 17
Colin Powell (1937) Former U.S. Secretary of State and retired four-star general
Source: It Worked For Me: In Life and Leadership (2012), p. xii
George Peacock (1791–1858) Scottish mathematician
Vol. II: On Symbolical Algebra and its Applications to the Geometry of Position (1845) Preface, p. iii
A Treatise on Algebra (1842)
Duncan Gregory (1813–1844) British mathematician
Source: Examples of the processes of the differential and integral calculus, (1841), p. 237; Lead paragraph of Ch. XV, On General Theorems in the Differential Calculus,; Cited in: James Gasser (2000) A Boole Anthology: Recent and Classical Studies in the Logic of George Boole,, p. 52
Isaac Asimov (1920–1992) American writer and professor of biochemistry at Boston University, known for his works of science fiction …
Quasar, Quasar, Burning Bright (1978), p. 235
General sources
Augustus De Morgan (1806–1871) British mathematician, philosopher and university teacher (1806-1871)
Author's Preface
On the Study and Difficulties of Mathematics (1831)
John Wallis (1616–1703) English mathematician
An Essay on the Art of Decyphering (1737)
Context: Partly out of my owne Curiosity, partly to satisfy the Gentleman's Importunity that did request it, I resolved to try what I could do in it: And having projected the best Methods I could think of for the effecting it, I found yet so hard a Task, that I did divers Times give it over as desperate: Yet, after some Intermissions, resuming it againe, I did at last overcome the Difficulty; but with so much Paines and Expense of Time as I am not willing to mention; though yet I did not repent of that Labour, when I had discovered thereby, that it was a Businesse, which though with much Difficulty, was yet capable to bee effected.<!--p.13