@TechReport{Wilke99,
   author=      "Thomas Wilke",
   title=       "C{TL}+ is exponentially more succinct than {CTL}",
   institution= "RWTH Aachen",
   year=        "1999",
   number=      "AIB-07-1999",
   url=         "http://aib.informatik.rwth-aachen.de/1999/1999-07.ps.gz",
}