@misc{indiciaeb01700a85bac,
  title = {Geomagnetic polarity epochs: new data from Olduvai Gorge, Tanganyika},
  author = {C. S. Grommé and R. L. Hay},
  year = {1967},
  doi = {10.1016/0012-821x(67)90110-0},
  url = {https://pubs.usgs.gov/publication/70010622},
  note = {Source identifier: 70010622}
}