The High-Beta Tokamak equilibrium code   is based on a somewhat unusual technique (in the field of MHD equilibrium calculations), namely conformal mapping theory.  Using this technique, the (arbitrarily shaped) cross section of the last closed flux surface is mapped to a circular disk, greatly facilitating the solution of equilibrium and stability problems.
- J.P. Goedbloed, Some remarks on computing axisymmetric equilibria, Computer Physics Communications 31, 2-3 (1984) 123
- J.P. Goedbloed & P.H. Sakanaka, Orthogonal and conformal mapping with application to MHD equilibrium and stability calculations, Transport Theory and Statistical Physics Volume 16, Issue 2-3 (1987)
- J.P. Goedbloed, Conformal mapping methods in two-dimensional magnetohydrodynamics, Computer Physics Communications 24, 3-4 (1981) 311-321