@misc{indiciaedc00606a542f,
  title = {Circular DNA.},
  author = {D R Helinski and D B Clewell},
  year = {1971},
  doi = {10.1146/annurev.bi.40.070171.004343},
  url = {https://pubmed.ncbi.nlm.nih.gov/4942224/},
  note = {Source identifier: 4942224}
}