An Archimedean Spiral with , having polar equation
References
Gray, A. Modern Differential Geometry of Curves and Surfaces.
Boca Raton, FL: CRC Press, pp. 69-70, 1993.
Lawrence, J. D. A Catalog of Special Plane Curves. New York: Dover, pp. 186 and 188, 1972.
Lockwood, E. H. A Book of Curves. Cambridge, England: Cambridge University Press, p. 175, 1967.
MacTutor History of Mathematics Archive. ``Lituus.''
http://www-groups.dcs.st-and.ac.uk/~history/Curves/Lituus.html.