@article{KolbMichaelisMoennichetal.2003,
  author    = {Kolb, Hans-Peter and Michaelis, Jens and M{\"o}nnich, Uwe and Morawietz, Frank},
  title     = {An operational and denotational approach to non-context-freeness},
  issn      = {0304-3975},
  year      = {2003},
  language  = {en}
}
@article{MichaelisMoennichMorawietz2001,
  author    = {Michaelis, Jens and M{\"o}nnich, Uwe and Morawietz, Frank},
  title     = {On Minimalist Attribute Grammars and Macro Tree Transducers},
  isbn      = {1-57586-359-6 ; 1-57586-57-x},
  year      = {2001},
  language  = {en}
}