Cajori, Florian. A History of Mathematics. New York: MacMillan and Co., 1894.

Coolidge,J.L. "The Unsatisfactory Story of Curvature." The American Mathematical Monthly. vol. 59, number 6. New York: McGraw-Hill Book Co., Inc, 1952.

Gamkrelidze, R.V. Encyclopaedia of Mathematical Sciences. Vol. 28. New York: Springer-Verlag, 1980.

Gauss, Karl Friedrich. General Investigations of Curved Surfaces of 1827 and 1825. Princeton: Princeton University Press, 1902.

Hill, Thomas. An Elementary Treatise on Curvature. Boston: James Monroe and Company, 1850.

Katz, Victor J. A History of Mathematics. New York: HarperCollins College Publishers, 1993.

Kline, Morris. Mathematical Thought From Ancient To Modern Times. New York: Oxford University Press, 1972.

McCleary, John. Geometry From a Differentiable Viewpoint. New York: Cambridge University Press, 1994.

Simpson, Thomas. The Doctrine and Application of Fluxions. London: Knight and Compton, 1805.

Struik, D.J. A Source Book In Mathematics. Princeton: Princeton University Press, 1986.

--. A Concise History of Mathematics. New York: Dover Publications, Inc., 1987.

Whiteside, D.T. The Mathematical Papers of Isaac Newton.n Vol. II. Cambridge: Cambridge University Press, 1969.