ocl and a syntax like:
ocl ts option spectral type
allows to make selection on the spectral type information.
The standard options are used to select clusters that have a spectral
type equal to (-eq), larger than (-gt), smaller
than (-lt) or inbetween (-i) given limits.
The output list is ordered according to the spectral type as a first key,
and coordinates as a second one. If the selection is made over two
spectral types, like ocl -i B8 A2, the sorted ouput will
present the A-type stars first due to dictionnary order.
ocl ts -i B4 B7 select clusters with spectral
type between B4 and B7