@article{Vidale1986,
  title={Complex polarization analysis of particle motion},
  author={Vidale, J. E.},
  journal={Bulletin of the Seismological Society of America},
  volume={76},
  number={5},
  pages={1393--1405},
  year={1986},
  publisher={Seismol Soc America},
  url={http://www.bssaonline.org/content/76/5/1393.short},
}
