@unpublished{DempwolffGuthmann1999,
  author  = {Ulrich Dempwolff and Andreas Guthmann},
  title   = {Applications of Number Theory to Ovoids and Translation Planes},
  institution = {Fachbereich Mathematik},
  series    = {Preprints (rote Reihe) des Fachbereich Mathematik},
  number    = {305},
  year    = {1999},
  url  = {http://nbn-resolving.de/urn:nbn:de:hbz:386-kluedo-8006},
}