TY  - RPRT
TI  - An updated rate-of-spread clock
AU  - Jeremy Kolaks
AU  - Keith W. Grabner
AU  - George Hartman
AU  - Bruce E. Cutter
AU  - Edward F. Loewenstein
PY  - 2005
UR  - https://pubs.usgs.gov/publication/70177757
ID  - 70177757
ER  -