Wikipedia contributors. (2024, April 22). Voltaire. In Wikipedia, The Free Encyclopedia. Retrieved May 1, 2024, from https://en.wikipedia.org/w/index.php?title=Voltaire&oldid=1220150579
Calculus Made Easy by Silvanus P. Thompson (gutenberg.org) Being a very-simplest introduction to those beautiful methods which are generally called by the terrifying names of the Differential Calculus and the Integral Calculus