 components of a
   corresponding DLA segment. A DLA descriptor also contains integers that
   act as forward and backward pointers to other DLA descriptors in the DLA
   file's doubly linked segment list.
<P>
 
   DLA descriptors are also data structures used as input and output
   arguments of DLA functions. They are also used extensively as arguments
   to DSK functions; the DSK subsystem is currently the only other SPICE
   subsystem where they're used. In the Fortran, IDL, and MATLAB SPICE
   Toolkits,