Henneberg surface
In differential geometry, the Henneberg surface is a non-orientable minimal surface named after Lebrecht Henneberg.
It has parametric equation
and can be expressed as an order-15 algebraic surface. It can be viewed as an immersion of a punctured projective plane. Up until 1981 it was the only known non-orientable minimal surface.
The surface contains a semicubical parabola and can be derived from solving the corresponding Björling problem.
