@TechReport{CleavelandParrowSteffen91,
  author =    "R. Cleaveland and J. Parrow and B. Steffen",
  title =     "The {C}oncurrency {W}orkbench: {A} {S}emantics {B}ased {T}ool for the {V}erification of {C}oncurrent {S}ystems",
  institution = "RWTH Aachen",
  year =      "1991",
  number =    "AIB-24-1991",
  url =       "http://aib.informatik.rwth-aachen.de/1991/1991-24.ps.gz",
}