@misc{indiciaeaabc53642fc1,
  title = {Localized instanton in four dimensions.},
  author = {GM O'Brien and DH Tchrakian},
  year = {1987},
  doi = {10.1103/physrevd.35.1468},
  url = {https://pubmed.ncbi.nlm.nih.gov/9957807/},
  note = {Source identifier: 9957807}
}