@article{FroSchw13,
  author    = {Andr{\'e} Frochaux and
               Nicole Schweikardt},
  title     = {A note on monadic datalog on unranked trees},
  journal   = {CoRR},
  volume    = {abs/1310.1316},
  year      = {2013},
  ee        = {http://arxiv.org/abs/1310.1316}
}