@inproceedings{Seidl04Counting,
  author = {Helmut Seidl and Thomas Schwentick and Anca Muscholl and Peter Habermehl},
  title = {Counting in {T}rees for {F}ree},
  booktitle = {Automata, Languages and Programming},
  editor = {Josep D\'iaz and Juhani Karhum\"aki and Arto Lepist\"o and Donald Sannella},
  month = {July},
  year = 2004,
  pages = {1136-1149},
  series = {Lecture Notes in Computer Science},
  volume = {3142},
  publisher = {Springer},
  address = {Turku, Finland},
}