The Free On-line Dictionary of Computing (30 December 2018):

Simulation Oriented Language

    (SOL) An ALGOL extension for discrete
   simulation by Donald Knuth and McNeley.

   ["SOL - A Symbolic Language for General Purpose System
   Simulation", D.E. Knuth et al, IEEE Trans Elec Comp,
   EC-13(4):401-408 (Aug 1964)].

   [Sammet 1969, p. 656].

   (1995-07-26)