PointGroupsBravaisClass( B )
PointGroupsBravaisClass( B [, norm ] )
where B is a finite integral matrix group, returns a list of representatives of those conjugacy classes of subgroups of B which are in the same Bravais class as B. These representatives are returned as parent groups, not subgroups. If B is a Bravais group, the list contains a representative of each point group in the Bravais class of B. If a second argument is present, which must be a list of elements of the normalizer of B in GL(d,Z), only subgroups inequivalent under conjugation with these elements are returned.
GAP 3.4.4