TY  - RPRT
TI  - Geomagnetic polarity epochs: age and duration of the olduvai normal polarity event
AU  - C. S. Grommé
AU  - R. L. Hay
PY  - 1971
DO  - 10.1016/0012-821x(71)90004-5
UR  - https://pubs.usgs.gov/publication/70010277
ID  - 70010277
ER  -