Kepler's Folium

$\begin{figure}\begin{center}\BoxedEPSF{KeplersFolium.epsf}\end{center}\end{figure}$

The curve with implicit equation

$\begin{displaymath}[(x-b)^2+y^2][x(x-b)+y^2]-4a(x-b)y^2. \end{displaymath}$

References