text: Each of the groups in this section has two cell structure diagrams, which are to be interpreted as follows (it is the shape that is significant, not the colour):
  On the right-hand side diagrams, different equivalence classes of symmetry elements are colored (and rotated) differently.
  The brown or yellow area indicates a fundamental domain, i.e. the smallest part of the pattern that is repeated.
  The diagrams on the right show the cell of the lattice corresponding to the smallest translations; those on the left sometimes show a larger area.