@misc{indiciae4d322fb71641,
  title = {Critically refracted waves in a spherically symmetric radially heterogeneous Earth model},
  author = {David P. Hill},
  year = {1973},
  doi = {10.1111/j.1365-246x.1973.tb02390.x},
  url = {https://pubs.usgs.gov/publication/70241580},
  note = {Source identifier: 70241580}
}