@misc{Schroeder2026U21,
  author = {Schroeder, Michael},
  title = {A Universal Turing Machine with 21 Instructions},
  year = {2026},
  month = sep,
  publisher = {Zenodo},
  version = {1.0},
  doi = {10.5281/zenodo.22957167},
  url = {https://doi.org/10.5281/zenodo.22957167}
}