TY  - RPRT
TI  - Secular variation in economic geology
AU  - Richard J. Goldfarb
AU  - Dwight Bradley
AU  - David L Leach
PY  - 2010
DO  - 10.2113/gsecongeo.105.3.459
UR  - https://pubs.usgs.gov/publication/70230185
ID  - 70230185
ER  -