@misc{indiciaed02472b88c3a,
  title = {Seismic vibration source},
  author = {Dowler, W. L. and Varsi, G. and Yang, L. C.},
  year = {1979},
  url = {https://ntrs.nasa.gov/citations/19790014508},
  note = {Source identifier: 19790014508}
}