p_surf.zip
contains an include file for POV-Ray 3.1 to create
surfaces like "Henneberg's surface":
x=2 sinh(u)cos(v) - 2/3 sinh(3u)cos(3v) y=2 sinh(u)cos(v) - 2/3 sinh(3u)sin(3v) z=2 cosh(2u)cos(2v) where 0 <= u <= 1; 0 <= v < 2pi
"Kuen's surface"
"Curlyhorn"
Klein bottle
Figure 8 Klein "bottle"