@TechReport{Sch\"urrWinterZ\"undorf95,
  author =    {Andy Sch\"urr and Andreas J. Winter and Albert Z\"undorf},
  title =     "Graph {G}rammar {E}ngineering with {PROGRES}",
  institution = "RWTH Aachen",
  year =      "1995",
  number =    "AIB-02-1995",
  url =       "http://aib.informatik.rwth-aachen.de/1995/1995-02.ps.gz",
}