-This draws the three-dimensional variant of the recursive Menger
-Gasket, a cube-based fractal object analagous to the Sierpinski
-Tetrahedron.
+The Menger Gasket is a cube-based recursive fractal object
+analagous to the Sierpinski Tetrahedron.
+
+https://en.wikipedia.org/wiki/Menger_sponge
+https://en.wikipedia.org/wiki/Sierpinski_carpet