Can anyone help me how the high symmetry points in the bandstructure are named. I know a few rules which are as listed below: * Points (and lines) inside the Brillouin zone are denoted with Greek letters. * Points on the surface of the Brillouin zone with Roman letters. * The center of the Wigner-Seitz cell is always denoted by a G. The same letters do not represent the same directions in different lattices. This gives some idea but not how the various directions are actually named. If the rules can be stated here, then good. If not please give some reference (book or article/paper) from which I can learn them and which can explain why they are named so. Are they listed in the International tables of crystallography? Thanks in advance.