tsl-1

from The Free On-line Dictionary of Computing (8 July 2008)

TSL-1

   Task Sequencing Language.  Language for specifying sequences
   of tasking events in Ada programs.

   ["Task Sequencing Language for Specifying Distributed Ada
   Systems", D.C. Luckham et al in PARLE: Parallel Architectures
   and Langs Europe, LNCS 259, Springer 1987, pp.444-463].