The results of a Korringa-Kohn-Rostoker calculation (performed by Bristol student Zsuzsanna Major during her Ph.D.) of the Fermi surface superimposed on the experimental data. The white arrow indicates a part of the Fermi surface thought to be very important in governing the nature of the superconductivity. This is a recent (2005) follow-up study to some previous work (S.B. Dugdale et al., Phys. Rev. Lett. 83 4824 (1999).)