@techreport{birkedal06sortings,
  author = {Lars Birkedal and S{\o}ren Debois and Thomas Hildebrandt},
  title = {Sortings for reactive systems},
  institution = {IT University of Copenhagen},
  number = {84},
  month = {March},
  year = {2006},
  note = {ISBN 87-7949-124-3}
}