@misc{indiciae57559cf05ae7,
  title = {Imaginary part in thermo field dynamics.},
  author = {Y Fujimoto and M Morikawa and M Sasaki},
  year = {1986},
  doi = {10.1103/physrevd.33.590},
  url = {https://pubmed.ncbi.nlm.nih.gov/9956663/},
  note = {Source identifier: 9956663}
}