@techreport{Vis97.cc,
  author      = {Visser, Eelco},
  title       = {Character Classes},
  year        = {1997},
  month       = {August},
  number      = {P9708},
  institution = {Programming Research Group, University of Amsterdam},
  url         = {http://adam.wins.uva.nl/~visser/syntax/sdf/charclasses/},
  urlpsgz     = {http://www.cs.uu.nl/people/visser/ftp/P9708.ps.gz},
  pubcat      = {techreport},
  project     = {ASF+SDF and SDF},
  category    = {non-refereed},
}