@misc{indiciae0f1d78b9e2e5,
  title = {Upper mantle structure - Are the low velocity layers thin?},
  author = {Bloch, S. and Hales, A. L.},
  year = {1969},
  url = {https://ntrs.nasa.gov/citations/19690044164},
  note = {Source identifier: 19690044164}
}