Commutative regular languages

C. P. Rupert. Commutative regular languages. SIGACT News, 22(4):48-49, 1991. [doi]

@article{Rupert91-0,
  title = {Commutative regular languages},
  author = {C. P. Rupert},
  year = {1991},
  doi = {10.1145/126546.126547},
  url = {https://doi.org/10.1145/126546.126547},
  researchr = {https://researchr.org/publication/Rupert91-0},
  cites = {0},
  citedby = {0},
  journal = {SIGACT News},
  volume = {22},
  number = {4},
  pages = {48-49},
}