@misc{indiciaede7a01998137,
  title = {Preliminary determination of epicenters; monthly listing; April-June 1998},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1999},
  doi = {10.3133/ofr98600b},
  url = {https://pubs.usgs.gov/publication/ofr98600B},
  note = {Source identifier: ofr98600B}
}