@misc{indiciae28a95761f6c6,
  title = {Lake Superior seismic experiment},
  author = {W. H. Jackson and B. L. Tibbetts},
  year = {1964},
  doi = {10.3133/ofr6489},
  url = {https://pubs.usgs.gov/publication/ofr6489},
  note = {Source identifier: ofr6489}
}