@article{Culik68,
  title = {Some theorems on labelled bracketings used in transformational grammars},
  author = {Karel Culík},
  year = {1968},
  url = {http://www.kybernetika.cz/content/1968/2/87},
  researchr = {https://researchr.org/publication/Culik68},
  cites = {0},
  citedby = {0},
  journal = {Kybernetika},
  volume = {4},
  number = {2},
  pages = {87-92},
}