@misc{indiciaefa2230720eb8,
  title = {Complex phase spaces and complex gauge groups in general relativity.},
  author = {PG Bergmann and GJ Smith},
  year = {1991},
  doi = {10.1103/physrevd.43.1157},
  url = {https://pubmed.ncbi.nlm.nih.gov/10013486/},
  note = {Source identifier: 10013486}
}